Vehicle guidance system for avoiding obstacles stored in memory

ABSTRACT

If an obstacle ( 74 ) is detected, its position is stored in obstacle memory unit ( 41 ) on the assumption that the obstacle ( 74 ) is common to a plurality of vehicles ( 2, 2 ). As vehicles ( 2, 2 ) pass by, the content of the obstacle memory unit ( 44 ) is updated. When the vehicles ( 2, 2 ) are supplied with position data of the respective goal point ( 72, 72 ), the vehicles ( 2, 2 ) are guided by their goal point ( 72, 72 ) in accordance with the content of the obstacle memory unit ( 41 ) so that they can avoid the obstacle ( 74 ). Vehicles can be thus guided to avoid obstacles by knowing the existence of obstacles in the working sites where the positions of obstacles are always different.

TECHNICAL FIELD

This invention relates to a vehicle guidance system, and particularly toa system suitable for applications in cases where a plurality ofunmanned off-road dump trucks are guided at a work site such as a mine.

BACKGROUND ART

Unmanned vehicle guidance systems are being broadly and practicallyimplemented which guide the movements of unmanned vehicles such asunmanned off-road dump trucks at mining sites of extensive area in theinterest of releasing from hard labor, lowering production costs, andreducing fuel consumption, etc.

These unmanned vehicles carry position measurement equipment that usesGPS (global positioning system) equipment or the like to measure travelpositions thereof. At a monitoring station that monitors a plurality ofunmanned vehicles, meanwhile, position data for travel courses that theunmanned vehicles are to travel over are determined by means of worksite surveying and/or teaching, and stored in memory. When an unmannedvehicle is sent such travel course position data via radiocommunications or the like, that vehicle measures its own position (anddirection) with the on-board position measuring equipment, and effectsvehicle steering control so that it successively reaches positions onthat travel course while comparing the measured current position withthe successive positions on the travel course.

One widely employed method of acquiring the travel course position datanoted here is a teaching method wherewith a manned vehicle designed forteaching is actually driven and the course run is stored in memory.

In such cases, the teaching vehicle actually travels over a course, andposition data are acquired for a course extending from a starting pointto a target point, or for a course that extends from the starting point,passes through the target point, and returns to a finish point, so thatunmanned vehicles will pass through the target points that they aresupposed to reach. Another method is to acquire only the position datafor the target point by teaching and then generate the courses to be runfrom those target point position data.

Consider, for example, the,case diagrammed in FIG. 8 where, at a miningsite, there exists a dumping area 65 where an unmanned vehicle 2 is toperform the operation of transporting earth and dumping that earth, thatis, an earth dumping operation. Position data for a travel course 71that passes through a target dumping point 72 in that dumping area 65are acquired by the teaching method.

Work sites such as mining sites of extensive area are usually unpaved,and the road surface conditions change from time to time in conjunctionwith the traveling of the unmanned vehicles 2. Also, during thetraveling of the unmanned vehicles 2, the rock and earth loaded thereonsometimes fall onto the road surface. It sometimes happens, therefore,that potholes and/or mud is formed on the travel course obtained byteaching, making it very difficult for the vehicles to pass through.There are also cases where rocks and the like appear on travel coursesobtained by teaching, making it impossible for vehicles to pass through.In this specification, the comprehensive term “obstacle(s)” is appliedto all obstacles to vehicle travel resulting from potholes, mud, orfallen load.

In such cases, it is necessary to again conduct teaching for a newtravel course that will avoid the obstacle or obstacles.

However, redoing the teaching operation every time the road surfacecondition changes or every time load falls from another unmanned vehicleresults in the loading operations or dumping operations beinginterrupted and causes a sharp decline in work efficiency.

In the face of this, a method is being adopted wherewith, instead ofavoiding conflict with the obstacles noted above by redoing the teachingoperation, an obstacle 74 is detected by an obstacle detector 34 carriedon the unmanned vehicle 2 while that vehicle is moving, as diagrammed inFIG. 9, so that each vehicle can individually alter the course it istraveling over.

In Japanese Patent Application Laid-Open No. 63-273916, Japanese PatentApplication Laid-Open. No. 3-113516, and Japanese Patent ApplicationLaid-Open No. 5-87608, for example, inventions are described wherewithobstacles ahead of a vehicle are detected by an obstacle detectorcarried by the vehicle, and the travel course is altered so as to avoidconflict with that detected obstacle.

Using the inventions described in the publications noted above, however,only obstacles in front of a vehicle within a range detectable by theobstacle detector can be detected. Other obstacles existing on thetravel course after course alteration cannot be detected ahead of time.For that reason, when a vehicle starts to negotiate an altered travelcourse, there is a danger that conflicts will occur with such otherobstacles.

The inventions described in the publications noted above are only ableto detect obstacles of shapes that are detectable by an obstacledetector. Conversely, obstacles of a shape that is undetectable by theobstacle detector cannot be detected. Obstacle detectors are generallycapable of detecting obstacles that bulge out from the road surface,that is, obstacles such as fallen load (rocks), and can alter the travelcourse so that such obstacles are avoided. They are not able, however,to detect potholes that constitute indentations in the road surface, orrough road surfaces, or mud or the like. For that reason, there is adanger that vehicles will run afoul of such obstacles because the travelcourse will not be altered to avoid them, rendering the vehicles unableto move.

A plurality of unmanned vehicles will be in operation at a work site.However, even if each of those plurality of unmanned vehicles carries anobstacle detector, there is no guarantee that every one of thatplurality of vehicles will always be able to safely detect the sameobstacle. More specifically, obstacle detectors generally make use ofmilliwave radar, laser radar, or visual sensors, wherewith the obstacledetection precision is affected by the S/N ratio.

Work sites such as mining sites tend to become dusty. Thus it happensthat such dust constitutes noise when obstacles are being detected byobstacle detectors, making it very difficult to distinguish betweenthose obstacles and the surrounding environment. It is thus possiblethat, depending on changes in the surrounding environment, even if anobstacle can be detected by the obstacle detector carried on oneunmanned vehicle, that same obstacle might not be detectable with theobstacle detector carried on another unmanned vehicle. There istherefore a danger that the unmanned vehicle that could not detect theobstacle will run afoul of that obstacle.

In Japanese Patent Application Laid-Open No. 10-38586, an invention isdescribed wherewith, instead of detecting obstacles ahead of vehicles byobstacle detectors, the obstacles are registered beforehand, and analarm is issued when a vehicle approaches such a pre-registered obstacleto alert the operator to be careful.

In the invention described in this publication, the positions ofobstacles to a snow removal vehicle are stored beforehand in a memorymedium carried on board the snow removal vehicle. Provision is made sothat, while the snow removal vehicle is in operation, the data in thatmemory medium are sequentially read out, and an alarm is issued when anobstacle stored in that memory medium is approached to alert theoperator to be careful.

According to the invention described in the publication noted above,only those obstacles that have been pre-stored in the memory medium canbe detected and avoided. Conversely, newly developed obstacles that havenot been pre-stored in the memory medium cannot be detected or avoided.

To be sure, the problem of overlooking obstacles will not occur inapplications in cases where fixed obstacles are detected, and no newones develop, as in snow removal vehicle operations, with respect toditches and road shoulders and the like that are covered with snow.

When the invention described in the publication noted above is employedat work sites such as mining sites of extensive area where pluralitiesof unmanned vehicles are operated, however, problems arise in that newlydeveloped obstacles are overlooked and already removed obstacles areerroneously detected as obstacles.

More specifically, at mining sites of extensive area, objects (load)fall from the unmanned dump trucks from time to time. And, even whensuch obstacles (load) do fall, they may be promptly discovered andremoved by a manned vehicle such as a bulldozer. There will also becases where another manned work vehicle such as a bulldozer or fueltruck or the like will be stopped on the travel course of an unmanneddump truck. In such cases, the manned work vehicle constitutes anobstacle to the unmanned vehicle. Also, the positions where such mannedvehicles that constitute obstacles stop change from time to time. Thusthe obstacles are not stationary or fixed at work sites such as thiswhere a plurality of vehicles is being operated. New obstacles willdevelop, or be removed, and the positions thereof will change from timeto time, as the vehicles travel about.

Accordingly, when the invention described in the publication noted aboveis employed, there will be cases where newly developed obstacles otherthan those obstacles pre-stored in the memory medium are overlooked,thus giving rise to the possibility that a vehicle will run afoul ofsuch obstacles. Problems will also arise when, conversely, obstaclesalready removed are erroneously recognized as existing obstacles andunnecessary course changes are made or the vehicle is stoppedunnecessarily.

In other words, the invention described in Japanese Patent ApplicationLaid-Open No. 10-38586 is not able to cope with work sites where theobstacles change in real time, such as work sites where pluralities ofvehicles are operated.

The objects of the present invention, which was devised in view of thesituation described in the foregoing, are as follows.

(1) To provide for altering the travel course when an obstacle develops,with good work efficiency (altering the travel course with better workefficiency than with methods based on teaching).

(2) To eliminate the overlooking of obstacles and the erroneousrecognition of obstacles even at work sites where the obstacles changein real time, such as at work sites where pluralities of vehicles arebeing operated.

(3) To make it possible to capture obstacles without fail, even whenthey are obstacles existing within a range undetectable by the obstacledetector, or are obstacles of an undetectable shape.

(4) To make it possible to capture objects without fail, irrespective ofnoise surrounding the obstacle or other surrounding environment.

Other objects are described next.

The teaching procedure described earlier exhibits great capability inoperations where the same course is traveled repeatedly. At sites wherethe shape of the course changes frequently, however, the operation ofproducing course data by teaching must be done frequently, wherefore thecapability thereof is severely limited.

In a loading area at a mining site, for example, the positions ofloading equipment such as wheel loaders or power shovels are subject tochange at any time as the work progresses. In a dumping area at a miningsite, on the other hand, dumping is not only done at a fixed dumpingfacility (pit), but the procedure of dumping while successively alteringthe dumping position within a dumping area having a certain breadth isalso employed.

With the teaching procedure described earlier, it is necessary to teacha new course every time the position of the loading equipment or thedumping position changes, and that necessity severely impairs thepersonnel reduction benefit of an unmanned dumping system.

In order to cope with changing work sites like this, the method ofaltering once prepared courses and then using them, and the method ofguiding the vehicles by radio control have been proposed.

Specifically, in Japanese Patent Application Laid-Open No. 5-257529, amethod is proposed wherewith, after guiding a vehicle by radio control,a course for returning to the circuit course (original course) isgenerated.

It is possible to guide a vehicle to any location using such radiocontrol, in like manner as in manual operations, but personnel are thenneeded to operate the radio control. When a vehicle is guided fromoutside using a joy stick or the like, moreover, a very difficult andonerous operation is required that involves continually switchingbetween the direction of advance of the vehicle and the operator's ownpoint of view, as has been demonstrated by actually employing radiocontrol equipment.

To avoid the difficulties of such radio control operations, there arecases also where most of the work is done by unmanned operations, butwhen loading operations are done, operators climb into vehicles andperform the operation.

A method has also been proposed, in Japanese Patent ApplicationLaid-Open No. 9-44243, wherewith courses are produced from a branchingpoint in a scheduled course (original course) using cubic curves.

This method exhibits higher utility in actual use than does the methodusing radio control, but it suffers shortcomings in that the rangewherein the vehicle can be guided is limited by the cubic curve, and inthat there is a possibility of conflict with a vehicle when an obstacleexists within the guidance range.

The occurrence of conflicts cannot be verified unless a vehicle isactually test-operated, wherefore adequate monitoring is necessaryduring operation, and it is also very difficult to use unless the worksite allows a sufficiently flat guidance range to be preparedbeforehand.

There is a proposal made in Japanese Patent Application Laid-Open No.8-101712 that takes conflicts with obstacles into consideration afterplanning vehicle travel routes. This involves teaching for straight linesegments and other simple segments but teaching with an actual vehiclefor complex segments where there is a great possibility of conflict.

With this method, teaching for the loading segments has to be repeatedas a loading operation progresses, so there is no hope of improvingutilization convenience.

Furthermore, a method has been proposed (in Japanese Patent ApplicationLaid-Open No. 1-173300) wherewith the shape of an extremely confinedcourse area such as a parking area is detected with a revolvingultrasound sensor, and the ideal steering angle for entering thatparking area is found from a database and indicated to the driver.

With that method, however, it is impossible to operate unmannedtraveling vehicles that move freely while changing the steering anglewithin course areas that are both large and complex while avoidingconflicts.

In other words, unlike a parking area, the shapes of and targetpositions in course areas at loading sites in mining facilities differover a very broad range. Also, it is very difficult in practice tocreate a database for finding one-to-one course data from the shape ofthat course area, etc., and hence a more general-purpose method isdeemed necessary.

Furthermore, in route searches for general articulated industrialrobots, the concept of a configuration coordinate system wherein theangle at each axis is taken in a coordinate axis is widely used. In viewof the fact that each robot axis can move independently, it is possiblefor a robot to move in a straight line passing through any two pointswithin that space. (Conversely, it is not always possible for a robot tomove between any two points given in three-dimensional space.) By usingthis space, the maze method and various other route search techniqueshave been devised.

In the space described above, if a route is first produced which willavoid conflict with obstacles, that route will always be negotiable.That is, it will be possible to effect route searches that considerobstacle avoidance only, giving no thought to the problem of routenegotiability.

This configuration coordinate system concept cannot be used in unmannedvehicles which operate with steering controls. That is, even if thepositions of two points in a plane, and directions of vehicle advance atthose position, are prescribed, an unmanned vehicle that only hasfunctions for moving forward and in reverse, and steering, cannot moveover a route that connects the positions noted above with straightlines.

That is, even if a route is planned which gives the priority to obstacleavoidance, it will be impossible for an ordinary vehicle that operateswith steering controls and the like, specifically a vehicle havingsteering mechanisms such as a front wheel steering mechanism, rear wheelsteering mechanism, four wheel steering mechanism, and articulation, tonegotiate that course.

In FIG. 37, for example, a route between two points is represented whichtakes an obstacle into consideration. In this case, however, it isclearly impossible for vehicle A to move.

Given the conditions diagrammed in FIG. 37, a route such as thatdiagrammed in FIG. 38 is desirable.

In order to resolve the problem described in the foregoing, there arecases where the vehicle mechanisms are modified and a vehicle isdesigned which is capable of moving in all directions. Extra steeringmechanisms not only involve increased costs, however, but high-speeddriving stability is lost, wherefore such are not suitable forapplications to unmanned vehicles used at mining sites where high-speedtravel is demanded.

In view of the situation described in the foregoing, an object of thepresent invention is to provide an unmanned vehicle guidance systemwherewith guidance courses can easily be prepared that are responsive tochanges in course area shape and changes in movement target positions,and wherewith vehicles can be prevented from conflicting with coursearea boundaries and excavation faces.

DISCLOSURE OF THE INVENTION

Thereupon, a first invention is a vehicle guidance system for guiding aplurality of vehicles, comprising:

memory means for storing positions of obstacles at a work site common tothe plurality of vehicles when that plurality of vehicle travelsimultaneously over that work site;

updating means for updating content stored in the memory means; and

guidance means for guiding the.plurality of vehicles based on thecontent stored in the memory means so that those vehicles do notconflict with the obstacles.

Based on the first invention, as diagrammed in FIG. 3 and FIG. 12(a),when an obstacle 74 has been detected, etc., the position of thatobstacle 74 is stored in the memory means 41, considering that positionas an obstacle 74 common to a plurality of vehicles 2, 2 . . . . Then,as the multiple vehicles 2, 2 . . . travel, the content stored in thememory means 41 is continually updated.

Guidance is effected, based on the content stored in the memory means41, so that there is no conflict with the obstacle 74. That is,conflicting objects are avoided by stopping before they are reached,etc.

According to this invention, as described in the foregoing, provision ismade so that the position of the obstacle 74 common to the plurality ofvehicles 2, 2 . . . is stored in the memory means 41, and so that thecontent stored in the memory means 41 is updated in conjunction with thetraveling of the plurality of vehicles 2, 2 . . . . Therefore, evenshould one vehicle overlook or erroneously recognize something as anobstacle, that which has been accurately judged by another vehicle willbe recorded as an obstacle. Accordingly, even if at a work site wherethe obstacles change in real time, as at a work site where multiplevehicles are traveling about, there will cease to be obstacles that areoverlooked and erroneous judgments of things as obstacles.

A second invention is a vehicle guidance system in which each of aplurality of vehicles is provided with vehicle position measurementmeans for measuring a current position of its own vehicle, when positiondata for target points that should be reached by each of the pluralityof vehicles are given, data are generated for travel courses that passthrough those target points and each of the plurality of vehicles isguided along its proper travel course while comparing the currentvehicle position measured by the vehicle position measurement means withpositions on the generated travel course,

the vehicle guidance system comprising:

memory means for storing positions of obstacles at a work site common tothe plurality of vehicles when the plurality of vehicles travelsimultaneously over that work site;

updating means for updating content stored in the memory means;

travel course generation means which, when position data on the targetpoints are given, generates data for travel courses that pass throughthose target points, based on the content stored in the memory means,such that there is no conflict with the obstacles; and

guidance means for guiding the plurality of vehicles, respectively,along the travel courses generated by the travel course generationmeans.

Based on the second invention, as diagrammed in FIG. 3 and FIG. 12(a),when an obstacle 74 has been detected, etc., the position of thatobstacle 74 is stored in the memory means 41, considering that positionas an obstacle 74 common to a plurality of vehicles 2, 2 . . . . Then,as the multiple vehicles 2, 2 . . . travel, the content stored in thememory means 41 is continually updated.

Then, when position data for the target points 72, 72 . . . for each ofthe plurality of vehicles 2, 2 . . . are given, data are generated fortravel courses 71′, 71′ . . . that pass through those target points 72,72 . . . , based on the content recorded in the memory means 41, so thatthere is no conflict with the obstacle 74. Then the plurality ofvehicles 2, 2 . . . , respectively, is guided along the travel courses71′, 71′ . . . .

According to this invention, as described in the foregoing, provision ismade so that the position of the obstacle 74 common to the plurality ofvehicles 2, 2 . . . is stored in the memory means 41, and so that thecontent stored in the memory means 41 is updated in conjunction with thetraveling of the plurality of vehicles 2, 2 . . . . Therefore, evenshould there be an obstacle that one vehicle overlooked, that which hasbeen accurately judged by another vehicle will be recorded as anobstacle. Accordingly, even if at a work site where the obstacles changein real time, as at a work site where a plurality of vehicles istraveling about, obstacles will no longer be overlooked.

Based on this invention, moreover, the position, of the obstacle 74common to the plurality of vehicles 2, 2 . . . is stored in the memorymeans 41, wherefore it becomes possible to perform the operation ofrevising the travel courses 71, 71 . . . for the plurality of vehicles2, 2 . . . easily and in a short time from the content recorded in thememory means 41. For that reason, the operation of revising the travelcourses 71, 71 . . . can be done with good work efficiency. Workefficiency will be dramatically improved compared to the teachingoperation wherewith a special teaching vehicle must be operated everytime an obstacle develops.

A third invention is a vehicle guidance system in which each of aplurality of vehicles is provided with vehicle position measurementmeans for measuring a current position of its own vehicle, when positiondata for target points that should be reached by each of the pluralityof vehicles and position data for a course area capable of beingtraveled by the plurality of vehicles are given, data are generated fortravel courses that travel inside that course area and pass throughthose target points and each of the plurality of vehicles is guidedalong its proper travel course while comparing the current vehicleposition measured by the vehicle position measurement means withpositions on the generated travel course;

the vehicle guidance system comprising:

memory means for storing positions of obstacles at a work site common tothe plurality of vehicles when that plurality of vehicle travelsimultaneously over that work site;

updating means for updating content stored in the memory means;

travel course generation means which, when position data on the targetpoints and position data on the course area are given, generates datafor the travel courses that travel inside the course area and passthrough the target points, based on the content stored in the memorymeans, such that there is no conflict with the obstacles; and

guidance means for guiding the plurality of vehicles, respectively,along the travel courses generated by the travel course generationmeans.

Based on the third invention, as diagrammed in FIG. 3 and FIG. 12(a),when an obstacle 74 has been detected, etc., the position of thatobstacle 74 is stored in memory means 41, considering that position asan obstacle 74 common to a plurality of vehicles 2, 2 . . . . Then, asthe multiple vehicles 2, 2 . . . travel, the content stored in thememory means 41 is continually updated.

Then, when position data for the target points 72, 72 . . . for each ofthe plurality of vehicles 2, 2 . . . and position data for the coursearea 65 are given, data are generated for travel courses 71′, 71′ . . .that travel inside the course area 65 and pass through those targetpoints 72, 72 . . . , based on the content recorded in the memory means41, so that there is no conflict with the obstacle 74. Then theplurality of vehicles 2, 2 . . . , respectively, is guided along thetravel courses 71′, 71′ . . . .

Based on this third invention, the same effectiveness as with the secondinvention is realized. Based on the third invention, however, thevehicle 2 is guided so that it does not conflict with the untravelablearea outside the course area 65.

A fourth invention is the third invention, comprising: display means fordisplaying the course area on a display screen; and

obstacle indication means for indicating positions of obstacles on thedisplay screen based on relative positional relationship thereof withthe course area on the display screen;

wherein the memory means stores the positions of obstacles on thedisplay screen indicated by the obstacle indication means as positionsof obstacles common to the plurality of vehicles; and

the updating means updates the content stored in the memory means everytime the position of an obstacle is newly indicated by the obstacledisplay means.

Based on the fourth invention, the same benefits as with the thirdinvention are realized.

Furthermore, based on the fourth invention, as diagrammed in FIG. 12(a),when an operator has discovered an obstacle 74, the position where theobstacle 74 appeared or disappeared can be indicated accurately on thescreen in a relative positional relationship with the course area(dumping area) 65 on the display screen 76.

Based on this fourth invention, provision is made so that the operatorvisually verifies the obstacle 74 to be an obstacle, wherefore even anobstacle 74 that exists in a range that cannot be detected by theobstacle detector 34 carried on an unmanned vehicle or an obstacle 74 ofa shape that cannot be detected (pothole, mud, rough road surface, etc.)can be judged to be an obstacle.

Based on this fourth invention, furthernore, because provision is madeso that an operator visually verifies the obstacle 74 to be an obstacle,obstacles 74 can be ascertained more definitely, irrespective of thesurrounding environment, as compared to when they are detected by anobstacle detector 34.

A fifth invention is the third invention, comprising: display means fordisplaying on a display screen the course area and, of the travelcourses generated by the travel course generation means, a traveledtravel course or courses that have already been traveled over by thevehicles; and

obstacle indication means for indicating positions of obstacles on thedisplay screen based both on relative positional relationship thereofwith the course area on the display screen and on relative positionalrelationship with the traveled travel course or courses on the displayscreen;

wherein the memory means stores the positions of obstacles on thedisplay screen indicated by the obstacle indication means as positionsof obstacles common to the plurality of vehicles; and

the updating means updates the content stored in the memory means everytime the position of an obstacle is newly indicated by the obstacledisplay means.

Based on the fifth invention, the same benefits as with the thirdinvention are realized.

Based on the fifth invention, furthermore, as diagrammed in FIG. 12(a),when an operator has discovered an obstacle 74, the position where theobstacle 74 appeared can be indicated on the screen in a relativepositional relationship with the course area (dumping area) 65 on/thedisplay screen 76.

At work sites at mining sites of extensive area, obstacles 74 such asrocks mainly come into being when load falls from a vehicle 2.Accordingly, such obstacles 74 will often be positioned on a traveledtravel course 71″ that a vehicle 2 has completed a run over.

Here, as diagrammed in FIG. 12(b), a traveled travel course 71″ is beingdisplayed on the display screen 76, wherefore the generation position ofan obstacle 74 such as a rock or the like can be determined even moreaccurately in a relative positional relationship with this traveledtravel course 71″. That is, an operator can revise the position of anobstacle 74 judged in the relative positional relationship with thecourse area 65 (dumping area), judging it to be positioned at 74′ on thetraveled travel course 71″, and thus accurately indicate the position ofthe obstacle 74.

Based on this fifth invention, because provision is made so that anoperator visually verifies the obstacle 74 to be an obstacle, obstacles74 can be ascertained more definitely, irrespective of the surroundingenvironment, as compared to when they are detected by an obstacledetector 34.

A sixth invention is the third invention, comprising: display means fordisplaying the course area on a display screen;

obstacle indication means for indicating positions of obstacles on thedisplay screen based on relative positional relationship thereof withthe course area on the display screen; and

revision means for revising the positions of obstacles indicated by theobstacle indication means, based on data on the traveled travel courseor courses over which the vehicles have already traveled, of the travelcourses generated by the travel course generation means;

wherein the memory means stores the obstacle positions revised by therevision means as positions of obstacles common to the plurality ofvehicles; and

the updating means updates the content stored in the memory means everytime an obstacle position newly indicated by the obstacle indicationmeans is revised by the revision means.

Based on the sixth invention, the same benefits as with the thirdinvention are realized.

Based on the sixth invention, furthermore, as diagrammed in FIG. 12(a),when an operator has discovered an obstacle 74, the position where theobstacle 74 appeared can be indicated on the screen in a relativepositional relationship with the course area (dumping area) 65 on thedisplay screen 76.

At work sites at mining sites of extensive area, obstacles 74 such asrocks mainly come into being when load falls from a vehicle 2.Accordingly, such obstacles 74 will often be positioned on a traveledtravel course 71″ that a vehicle 2 has completed a run over.

Here, as diagrammed in FIG. 12(b), the position where an obstacle 74appeared, such as a rock or the like, indicated by an operator, isautomatically revised to the accurate position 74′, based on positiondata for the traveled travel course 71″.

Based on this sixth invention, because provision is made so that anoperator visually verifies the obstacle 74 to be an obstacle, obstacles74 can be ascertained more definitely, irrespective of the surroundingenvironment, as compared to when they are detected by an obstacledetector 34.

A seventh invention is the first invention or the second invention orthe third invention, in which some or all of the plurality of vehiclescomprise obstacle detection means for detecting obstacles; the vehicleguidance system further comprising:

obstacle position measurement means for measuring positions of thoseobstacles based on position of a vehicle when an obstacle has beendetected by the obstacle detection means; and

wherein the memory means stores the positions of obstacles measured bythe obstacle position measurement means as positions of obstacles commonto the plurality of vehicles; and

the updating means updates the content stored in the memory means, basedon the position of a new obstacle measured by the obstacle positionmeasurement means, every time a new obstacle is detected by the obstacledetection means.

Based on the seventh invention, the same benefits are realized as withthe first invention or the second invention or the third invention.

Based on the seventh invention, the following benefit is also realized.

That is, based on the seventh invention, as diagrammed in FIG. 9, anobstacle 74 detected by one vehicle 2 will be stored in the memory means41 as an obstacle 74 to other unmanned vehicles 2. Hence another vehicle2 will be able to avoid the obstacle 74 without fail, even if thatobstacle 74 could not be detected by the obstacle detection means 34carried on board that other vehicle 2. In other words, even in caseswhere the obstacle detection means 34 of another vehicle 2 fail oroperate uncertainly, or where the obstacle 74 cannot be detectedprecisely due to the influence of the surrounding environment, thatother vehicle 2 can nevertheless safely avoid the obstacle 74.

An eighth invention is the first invention or the second invention orthe third invention, in which some or all of the plurality of vehiclescomprise:

road surface condition detection means for detecting a road surfacecondition; and

determination means for determining that a current road surface is anobstacle based on the road surface condition detected by the roadsurface condition detection means;

wherein the memory means stores position of a vehicle at the time whenthe current road surface was determined to be an obstacle by thedetermination means as position of an obstacle common to the pluralityof vehicles; and

the updating means updates the content stored in the memory means everytime the determination means determines a new obstacle.

Based on the eighth invention, the same benefits are realized as withthe first invention or the second invention or the third invention.

Based on the eighth invention, the following benefit is also realized.

That is, based on this eighth invention, a vehicle 2 determines from thecondition of the road surface over which it travels that that is anobstacle 74, wherefore even an obstacle 74 that cannot be detected bythe obstacle detection means 34 (cf. FIG. 9) carried on the vehicle(such as mud, a pothole, or rough road surface, etc.) can be determinedto be an obstacle.

A ninth invention is the first invention or the second invention or thethird invention, in which some or all of the plurality of vehiclescomprise:

reception means for receiving signals from other manned vehiclesindicating that an obstacle exists in vicinity of its own vehicle;

transmission means for transmitting signals indicating position of itsown vehicle when a signal is received indicating that an obstacle existsin vicinity of its own vehicle; and

obstacle position measurement means for receiving signals indicating avehicle position transmitted from the transmission means and formeasuring positions of obstacles near that vehicle based on the vehicleposition received;

wherein the memory means stores the positions of obstacles measured bythe obstacle position measurement means as positions of obstacles commonto the plurality of vehicles; and

the updating means updates the content stored in the memory means, basedon the position of a new obstacle measured by the obstacle positionmeasurement means, every time a signal is received by the receptionmeans indicating that a new obstacle exists.

Thus, based on the ninth invention, the position of an obstacle 74 ismeasured on the basis of the position of a vehicle 2 that has been senta signal indicating the presence of an obstacle near that selfsamevehicle, that is, more specifically, that has been sent a stop command,and those data are stored in the obstacle memory unit 41.

Based on the ninth invention, the same benefits are realized as with thefirst invention or the second invention or the third invention.

A tenth invention is the first invention or the second invention or thethird invention, wherein, when a manned or unmanned work vehicle havingvehicle position measurement means for measuring position of its ownvehicle is present inside an area traveled over by the plurality ofvehicles, the memory means stores the position of the work vehiclemeasured by the vehicle position measurement means as position of anobstacle common to the plurality of vehicles, and the updating meansupdates the content stored in the memory means every time the positionof the work vehicle is altered by the vehicle position measurementmeans.

In other words, there are times when a work vehicle such as a mannedvehicle 20 or loading machine 14 or the like becomes an obstacle to thetraveling of a plurality of unmanned vehicles 2, 2 . . . , as diagrammedin FIG. 7.

Thereupon, as diagrammed in FIG. 3, the measured positions transmittedfrom the work vehicles 20 and 14 are stored as the positions ofobstacles 74 in the memory means 41. Then, every time the measuredpositions of the work vehicles 20 and 14 change, as they may at anytime, the content stored in the memory means 41 is updated.

Then, based on the content stored in the memory means 41, the vehicles 2are guided so that they avoid the obstacles 74.

Based on the tenth invention, the same benefits are realized as with thefirst invention or the second invention or the third invention.

An 11th invention is the tenth invention, wherein the updating meansupdates the content stored in the memory means every time the positionsof the work vehicles are successively changed in conjunction withtraveling of the work vehicles.

Based on the 11th invention, the updating of the stored positions of theobstacles 74 is done at any time, so long as the vehicle positions arebeing changed, irrespective of whether the work vehicles 20 and 14 aretravelling or stopped.

A 12th invention is the tenth invention, wherein the updating meansupdates the content stored in the memory means every time the workvehicle stops traveling and stopped position of that work vehicle ischanged.

Based on the 12th invention, the updating of the stored positions of theobstacles 74 is not done while the work vehicles 20 and 14 aretraveling, but only when those work vehicles 20 and 14 are stopped.

A 13th invention is a vehicle guidance system comprising: vehicleposition measurement means for measuring a current position of its ownvehicle, and being constructed such that, when position data for targetpoints that should be reached by the vehicle and position data for acourse area where the vehicle can travel are given, data for a travelcourse that enables the vehicle to travel inside the course area and topass through the target points are generated; and the own vehicle isguided over that travel course while comparing current vehicle positionsmeasured by the vehicle position measurement means and position on thegenerated travel course;

the vehicle guidance system comprising:

indication means for indicating positions of target points inside thecourse area;

indication means for indicating the position of a movement startingpoint inside the course area, the direction of a vehicle at the movementstarting point, the position of a target point inside the course area,and the direction of a vehicle at the target point;

travel course generation means for generating travel course datawherewith the vehicle departs the movement target point in the indicatedvehicle direction, alters the direction of advance thereof, reversingdirection at one or more direction reversal points, and, arrives at thetarget point in the indicated vehicle direction, so that, when positiondata indicating the boundary line of the course area are given, and theposition of the movement starting point, the vehicle direction at themovement starting point, the position of the target point, and thevehicle direction at the target point are indicated by the indicationmeans, the vehicle can travel over the interior enclosed by the boundaryline of the course area and also turn around with a turning radius equalto or greater than the minimum turning radius of the vehicle; and

guidance means for guiding the vehicle over the travel course generatedby the travel course generation means.

Based on the 13th invention, travel courses can easily be generated thatcope with changes in the shape of the course area and changes in thepositions and directions of the target points, without performing travelcourse teaching using an actual vehicle.

Also, because travel courses are generated so that the vehicles travelinside the course area, vehicles are prevented before the fact fromconflicting with course area boundaries or excavation faces.

A 14th invention is an unmanned vehicle guidance system for guidingunmanned vehicles over guidance courses based on travel positions ofthose unmanned vehicles measured by travel position measurement meansand course data defining guidance courses for the unmanned vehicles; theunmanned vehicle guidance system comprising:

means for inputting a shape of a course area;

means for respectively indicating the position of a movement startingpoint and the direction of advance of the unmanned vehicle at thatposition, and the position of a movement target point and the directionof advance of the unmanned vehicle at that position;

means for producing course data wherewith the indicated position and thedirection of advance are satisfied at the movement starting point and atthe movement target point, and wherewith the direction of advance of theunmanned vehicle changes at one or more direction reversal pointsprovided between the movement starting point and the movement targetpoint;

means for producing course data wherewith the indicated position anddirection of vehicle advance are satisfied at the position of themovement starting point and at the movement target point;

means for inferring conflicts between the course area and the unmannedvehicle when the unmanned vehicle is made to travel over a guidancecourse defined by the produced course data, based on data relating tothe unmanned vehicle; and

course data alteration means for altering the course data when aconflict has been inferred.

Based on the 14th invention, guidance courses can easily be generatedthat cope with changes in the shape of the course area and changes inmovement target positions, without performing guidance course teachingusing an actual vehicle.

Moreover, in addition to inferring conflicts between unmanned vehiclestraveling over the generated guidance courses and the boundaries of thecourse area, the course data are altered when such a conflict has beeninferred, Accordingly, conflicts between unmanned vehicles and coursearea boundaries or excavation faces can be prevented before the fact.

A 15th invention is the 14th invention wherein the means for producingcourse data comprises:

means for generating position of an intermediate point in the guidancecourse inside the course area and direction of vehicle advance at thatposition; and

means for connecting position of the movement starting point, positionof the intermediate point, and position of the movement target point,with a circular arc or arcs and/or straight line or lines, so as to passthrough each of those positions, and such that the direction of vehicleadvance at each of those positions coincides either with direction of atangent to such circular arc or arcs or with direction of such straightline or lines;

wherein the course data alteration means alters the course data byaltering the position of the intermediate point when the conflict hasbeen inferred.

Based on this 15th invention, the guidance course is produced using anintermediate point, wherefore it is possible easily to generate a routethat reverses direction at the intermediate point. As a consequence,routes can be freely planned that contain direction reversals.

Moreover, guidance courses are produced by connecting the position ofthe movement starting point, the position of the intermediate point, andthe position of the movement target point, by circular arcs, tangents,or both, wherefore the guidance course can be produced efficiently.

A 16th invention is the 14th invention wherein the means for producingcourse data comprises:

means for generating position of an intermediate point in the guidancecourse inside the course area and direction of vehicle advance at thatposition; and

means for connecting position of the movement starting point, positionof the intermediate point, and position of the movement target point,with a spline curve, so as to pass through each of those positions, andsuch that direction of vehicle advance at each of those positionscoincides with direction of a tangent to the spline curve;

wherein the course data alteration means alters the course data byaltering the position of the intermediate point when such conflict hasbeen inferred.

Based on the 16th invention, the same benefits are realized as with the15th invention.

A 17th invention is the 14th invention wherein the means for producingthe course data comprises:

means for generating position of an intermediate point in the guidancecourse inside the course area and direction of vehicle advance at thatposition; and

means for connecting position of the movement starting point, positionof the intermediate point, and position of the movement target point,with a spline curve and a circular arc, or with a spline curve and astraight line or lines, so as to pass through each of those positions,and such that direction of the vehicle advance at each of thosepositions coincides with direction of a tangent to that spline curve,direction of a tangent to such circular arc, or direction of suchstraight line or lines;

wherein the course data alteration means alters the course data byaltering the position of the intermediate point when such conflict hasbeen inferred.

By this 17th invention also, the same acting benefits are realized aswith the 15th invention.

An 18th invention is either the 15th or the 17th invention, wherein themeans for producing the course data comprises:

evaluation means for evaluating the course data using distances betweenthe guidance course and boundaries of the course area; and

selection means for selecting course data having best evaluation valuesout of a plurality of generated course data.

Based on this 18th invention, course data are evaluated, and thosecourse data having the best evaluation values are selected, wherefore itis possible to evaluate and select course data wherewith conflict willnot occur between the unmanned vehicles and the boundaries of the coursearea.

A 19th invention is either the 15th or the 17th invention, wherein themeans for producing the course data comprises:

evaluation means for evaluating the course data using a function betweendistances between the guidance course and boundaries of the course area,and minimum radius of the guidance course; and

selection means for selecting course data having best evaluation valuesout of a plurality of generated course data.

Based on this 19th invention, it is possible to evaluate and selectcourse data wherewith conflict will not arise between the unmannedvehicles and the boundaries of the course area, and wherewith theturning of the unmanned vehicles will not be hindered.

A 20th invention is an unmanned vehicle guidance system for guidingunmanned vehicles over guidance courses based on travel positions ofthose unmanned vehicles measured by travel position measurement meansand course data defining guidance courses for the unmanned vehicles; theunmanned vehicle guidance system comprising:

means for inputting shape of a course area;

means for producing course data;

means for inferring conflicts between the course area and the unmannedvehicle when the unmanned vehicle is made to travel over a guidancecourse defined by the produced course data, based on data relating tothe unmanned vehicle;

course data alteration means for altering the course data when theconflict has been inferred; and

mode setting means for setting an automatic operation mode when theunmanned vehicle is being guided using the generated course data, andfor setting a measurement mode when shape of the course area is beinginput.

Based on this 20th invention, an automatic operation mode or ameasurement mode can be selectively set, wherefore such problems as anunmanned vehicle operating automatically while in the measurement mode,or a course area shape being input when in automatic operation can beavoided. An operator can selectively set either of those modes,moreover, so work efficiency is enhanced.

A 21st invention is an unmanned vehicle guidance system for guidingunmanned vehicles over guidance courses based on travel positions ofthose unmanned vehicles measured by travel position measuring means andcourse data defining guidance courses for the unmanned vehicles, theunmanned vehicle guidance system comprising:

means for inputting shape of a course area;

means for producing course data;

mode setting means for causing can unmanned vehicle be guided using thegenerated course data when the automatic operation mode has been set,and for collecting course area shape data by causing the unmannedvehicle be guided along a course area and detecting positions traveledby the unmanned vehicle when a measurement mode has been set.

means for recognizing a shape change zone of the course area; and

course area shape updating means for updating shape of the course areaso that the course area shape is altered only in the zone whose shapehas been changed.

Based on this 21st invention, a shape change zone is recognized, and theshape a of the course area is updated only in that shape change zone,wherefore the frequency of course area shape input operations can bereduced to the extent possible.

A 22nd invention is the 21st invention wherein the means for recognizingthe shape change zone of the course area comprises:

a moving body for measuring that moves through the course area;

movement position measurement means for measuring movement position ofthe moving body for measuring; and

means for specifying the shape change zone based on the movementposition of the moving body for measuring and an area occupied by thatmoving body.

Based on this 22nd invention, the shape change zone is specified on thebases of the movement position of the moving body for measuring and thearea occupied by the moving body. Accordingly, if the course area is amining operation area, for example, a work machine for performing suchoperations as loading in the course area can be used as the moving bodyfor measuring.

A 23rd invention is the 21st invention wherein the means for recognizingthe shape change zone of the course area comprises:

position measurement means for measuring three-dimensional positions ofdigging unit of a work machine for digging operations in the coursearea;

ground height measurement means for measuring initial ground height inthe course area; and

means for specifying the shape change zone of the course area based onposition of the digging unit and area occupied thereby when height ofthe digging unit and the initial ground height coincide.

Based on this 23rd invention, changes in the course area are detectedfrom the fact that the height of the digging unit of a work machine forperforming digging. operations has coincided with the ground height inthe course area, and the shape change zone is specified based on thedigging unit position and area occupied. As a consequence, the shapechange zone can be specified without provided special measurement means.

A 24th invention is any one of the 14th, 20th, or 21st invention,wherein the travel position measurement means is a GPS, and means forinputting shape of the course area comprises:

means for switching a position measured by the GPS to a positionmeasured at left edge or right edge of the unmanned vehicle; and

indication means for indicating whether to switch to position measuredat the left edge or to position measured at the right edge.

Based on this 24th invention, a position measured by the GPS is switchedto a position measured either at the left edge or right edge of theunmanned vehicle, wherefore, by causing the unmanned vehicle to travelwhile bringing either the left edge or the right edge of the unmannedvehicle up to the boundary of the course area, the shape of the coursearea can be precisely input by a so-called teaching procedure.

A 25th invention is any one of the 14th, 20th, or 21st inventions,wherein the travel position measurement means is a GPS, and means forinputting shape of the course area comprises means for selectivelyaltering position of antenna of the GPS to left edge or right edge ofthe unmanned moving body.

Based on the 25th invention, the position of the GPS antenna can beselectively altered between the left edge and right edge of the unmannedmoving body, wherefore, by causing the unmanned vehicle to travel whilebringing either the left edge or the right edge of the unmanned vehicleup to the boundary of the course area, the shape of the course area canbe precisely input by a so-called teaching procedure.

A 26th invention is the 13th invention wherein the vehicle is anunmanned vehicle that is loaded with a load by a loading machine, andthe course area position data are updated by excluding a certain areareferenced to current position of the loading machine from currentcourse area.

Based on this 26th invention, as diagrammed in FIG. 40(a), by excludinga certain area 14 b based on the current position of the loading machine14 from the current course area 1, the position data for the course area1 (course area 1 shape) are updated. That is, even if the loadingmachine 14 does not comprise a device for measuring the bucket position,updating the position data for the course area 1 can be performedaccurately so long as a device is provided for measuring the currentposition of the loading machine 14.

A 27th invention is the 26th invention wherein the certain area excludedfrom the current course area is an area within reach of the loadingmechanism of the loading machine.

Based on this 27th invention, as diagrammed in FIG. 40(a), an area 14 bwithin a range reachable by the loading mechanism (arm) of the loadingmachine 14 from the current position of the loading machine 14 isdetermined, that area 14 b is excluded from the course area 1, andthereby the position data for the course area 1 (course area 1 shape)are updated. In other words, even if the loading machine 14 is notequipped with a device for measuring the bucket position, updating theposition data for the course area 1 can be performed accurately so longas a device is provided for measuring the current position of theloading machine 14.

A 28th invention is the 26th invention wherein the certain area excludedfrom the current course area is inside an area within reach of theloading mechanism of the loading machine, and an area of about size ofmain body of the loading machine.

Based on this 28th invention, as diagrammed in FIG. 40(a), an area 14 aof about the size of the main body of the loading machine 14, inside thearea 14 b within the range reachable by the loading mechanism (arm) ofthe loading machine 14, is found from the current position of theloading machine 14, that area 14 a is excluded from the current coursearea 1, and thereby the position data of the course area 1 (course area1 shape) are updated. In other words, even if the loading machine 14 isnot equipped with a device for measuring the bucket position, updatingthe position data for the course area 1 can be performed accurately solong as a device is provided for measuring the current position of theloading machine 14.

A 29th invention is the 26th invention, wherein the certain areaexcluded from the current course area is inside an area within reach ofthe loading mechanism of the loading machine, and an area that islocated at a constant distance from the boundary of the course area.

Based on this 29th invention, as diagrammed in FIG. 41, an area 14 csuch that the distance from the boundary 1 a of the course area 1 isconstant, inside the area 14 b within the range reachable by the loadingmechanism (arm) of the loading machine 14, is found from the currentposition of the loading machine 14, that area 14 c is excluded from thecurrent course area 1, and thereby the position data of the course area1 (course area 1 shape) are updated. In other words, even if the loadingmachine 14 is not equipped with a device for measuring the bucketposition, updating the position data for the course area 1 can beperformed accurately so long as a device is provided for measuring thecurrent position of the loading machine 14.

A 30th invention is the 13th invention, wherein the vehicle is anunmanned vehicle that is loaded with a load by a loading machine;relative position indication means for indicating relative positionsrelative to the loading machine is provided; and position data for thecourse area are updated by excluding an area referenced to positionsindicated by the relative position indication means from current coursearea.

Based on the 30th invention, relative positions (bucket positions)relative to the loading machine 14 are indicated by the relativeposition indication means, and areas based on those indicated positionsare excluded from the current course area 1, whereby the position dataof the course area 1 (course area 1 shape) are updated. In other words,in cases where the form of the excavation work lacks a certainregularity, a range that should be excluded from the course area 1 canbe directly indicated by the operator, and the position data for thecourse area 1 accurately updated.

A 31st invention is the 13th invention, wherein the.vehicle is anunmanned vehicle that is loaded with a load by a loading machine, andposition data for the course area are updated by adding, to currentcourse area, an area within range occupied by the unmanned vehicle at atarget point that should be reached by the unmanned vehicle.

Based on this 31st invention, as diagrammed in FIG. 39(a), from thetarget point which the unmanned vehicle 2 should reach is found an area2 a within the range a occupied by the unmanned vehicle 2 at the targetpoint, and that occupation range area 2 a is added to the current coursearea 1, thereby updating the course area 1 position data (course area 1shape). In other words, even if the loading machine 14 is not equippedwith a device for measuring the bucket position, updating the positiondata for the course area 1 can be performed accurately so long as adevice is provided for measuring the current position of the loadingmachine 14 (that is, the target point of the unmanned vehicle 2).

A 32nd invention is the 13th invention wherein the vehicle is anunmanned vehicle that is loaded with a load by a loading machine, andposition data for the course area are updated either by excluding acertain area referenced to current position of the loading machine fromcurrent course area, or by adding area within range occupied by theunmanned vehicle at target point that should be reached by the unmannedvehicle to current course area.

Based on this 32nd invention, as diagrammed in FIG. 40(a), the coursearea 1 position data (course area 1 shape) are updated by excluding acertain area 14 b based on the current position of the loading machine14 from the current course area 1, or, alternatively, as diagrammed inFIG. 39(a), the course area 1 position data (course area 1 shape) areupdated by finding, from the target point that the unmanned vehicle 2should reach, an area 2 a within the range occupied by the unmannedvehicle 2 at the target point, and adding that area 2 a within thatoccupied range to the course area 1. In other words, even if the loadingmachine 14 is not equipped with a device for measuring the bucketposition, updating the position data for the course area 1 can beperformed accurately so long as a device is provided for measuring thecurrent position of the loading machine 14 (that is, the target point ofthe unmanned vehicle 2).

A 33rd invention is the 32nd invention, further comprising selectionmeans for selecting whether the course area is to be expanded orcontracted, according to type of work being done by the loading machine,wherein the course area position data are subjected to updatingprocessing according to results of selection made by the selectionmeans.

Based on the 33rd invention, selection means for selecting whether thecourse area 1 is to be expanded or contracted, according to the workform of the loading machine 14, are also comprised, and the course area1 position data are subjected to updating processing according to theresults of the selection made by those selection means.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of the data flow in an embodiment aspect;

FIG. 2 is a block diagram of the configuration of an unmanned vehicle;

FIG. 3 is a block diagram of the configuration of a monitoring station;

FIG. 4 is a block diagram of the configuration of a loading machine;

FIG. 5 is a block diagram of the configuration of a manned vehicle;

FIG. 6 is a conceptual diagram exemplifying travel course generation;

FIG. 7 is a diagram representing the entirety of a course area;

FIG. 8 is a diagram representing what goes on at a work site;

FIG. 9 is a diagram representing how an obstacle is detected;

FIG. 10 is a diagram representing the positional relationship between anobstacle and a travel course;

FIG. 11 is a diagram representing the positional relationship between anobstacle and a travel course;

FIGS. 12(a) and 12(b) are diagrams representing a display screen;

FIG. 13 is a block diagram, of the configuration of a control systemdeployed in an unmanned dump truck;

FIG. 14 is a flowchart exemplifying procedures for generating a guidancecourse;

FIG. 15 is a conceptual diagram exemplifying the shape of a course area;

FIG. 16 is a diagram representing an aspect of guidance coursegeneration;

FIG. 17 is a diagram representing an aspect of guidance coursegeneration;

FIG. 18 is a diagram representing an aspect of guidance coursegeneration;

FIG. 19 is a diagram representing an aspect of guidance coursegeneration;

FIG. 20 is a diagram representing an aspect of guidance coursegeneration;

FIG. 21 is a diagram representing an aspect of guidance coursegeneration;

FIG. 22 is a diagram representing an aspect of guidance coursegeneration;

FIG. 23 is a diagram representing an aspect of guidance coursegeneration;

FIG. 24 is a diagram representing an aspect of guidance coursegeneration;

FIG. 25 is a diagram representing an aspect of guidance coursegeneration;

FIG. 26 is a diagram representing an aspect of guidance coursegeneration;

FIG. 27 is a plan representing the positions wherein a GPS antenna isdeployed;

FIG. 28 is a flowchart of GPS-based measured position switchingprocessing;

FIG. 29 is a conceptual diagram indicating the position of a loadingmachine in a course area;

FIG. 30 is a conceptual diagram representing how a loading machine movesin a course area;

FIG. 31 is a conceptual diagram representing the shape of an updatedcourse area;

FIG. 32 is a block diagram of the configuration of a control systemdeployed in a loading machine;

FIG. 33 is a flowchart exemplifying a course area updating procedure;

FIG. 34 is a conceptual diagram representing how a power shovel digs;

FIG. 35 is a block diagram of the configuration of a control systemdeployed in a power shovel;

FIG. 36 is a flowchart exemplifying a course area updating procedure;

FIG. 37 is a conceptual diagram of one example of a route that cannot benegotiated;

FIG. 38 is a conceptual diagram of one example of a route that can benegotiated;

FIGS. 39(a), 39(b), and 39(b) are diagrams for describing how a coursearea is expanded;

FIGS. 40(a) and 40(b) are diagrams for describing how a course area iscontracted; and

FIG. 41 is a diagram for describing how a coarse area is contracted.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment aspects of the vehicle guidance system relating to thepresent invention are now described with reference to the drawings.

To begin with, embodiment aspects wherewith conflict with an obstaclecan be avoided are described.

FIG. 7 represents the entirety of a work site for an embodiment aspect.In this embodiment aspect, it is supposed that a plurality of unmannedvehicles (dump trucks) 2, 2 . . . is engaged in loading operations forloading rock or earth containing ore in a loading area 73 at a miningsite of extensive area, that those unmanned vehicles 2, 2 . . . travelat high speed over a travel course area 67, and that they engage indumping operations for dumping the earth in a dumping area 65. In thiscase, this plurality of unmanned vehicles 2, 2 . . . is guided over atravel course 71 generated for each vehicle, as will be describedsubsequently. The loading area 73, travel course area 67, and dumpingarea 65 constitute the course area 68. By course area 68, then, is meantthat area over which an unmanned vehicle 2 is able to travel. The areasoutside the course area 68 are areas such as cliffs or excavation faceswhere it is impossible for a vehicle to travel, as diagrammed in FIG. 8.

Besides the plurality of unmanned vehicles 2, 2 . . . , a loadingmachine 14 and a manned vehicle 20 are also traveling inside the coursearea 68. The loading machine 14 is also a manned vehicle driven by anoperator, but to facilitate the description it is distinguished from themanned vehicle 20.

The loading machine 14 is a manned work machine that digs ore in theloading area 73 (excavation site) and loads that excavated ore (earth)onto the unmanned vehicle 2. Examples of such a machine are excavatorsand wheel loaders. The vehicle position of the loading machine 14 issubject to change at any time in conjunction with the progress of theexcavation operation.

The manned vehicle 20 is a manned work vehicle, driven by an operator,that performs various work other than the loading work described above.Examples thereof include manned dump trucks, bulldozers, road graders,water spraying vehicles, fuel supply vehicles, and four-wheel drivevehicles for performing teaching operations.

If the manned vehicle 20 is a bulldozer, for example, as diagrammed inFIG. 8, it will perform the work of dumping and otherwise handling earthdumped by an unmanned vehicle 2 in the dumping area 65 (dumping ground).As with the loading machine 14, the vehicle position of the mannedvehicle 20 is also subject to change at any time as the work progresses.

As the work is advanced by the loading machine 14 and manned vehicle 20described in the foregoing, the positions and shapes of the loading area14 and dumping area 65 also changes. That is because the position andshape of the excavation face and cliff and so forth change inconjunction with the work. The position and shape of the travel coursearea 67 may also change due to changes in the position and shape of theroad shoulder as the work advances.

Thus the position and shape of the course area 68 are subject to changeat any time as the work progresses.

The interior of the course area 68 is unpaved. Therefore, the roadsurface condition is subject to change at any time as the plurality ofunmanned vehicles 2, 2 . . . travels over it. The rock loaded on theunmanned vehicles 2 also sometimes falls onto the road surface as theunmanned vehicle 2 travels. Hence potholes and mud are formed on thetravel course of the unmanned vehicle 2, sometimes making it verydifficult for vehicles to negotiate. Rocks may also appear on the travelcourse such as make it impassable to vehicles. Accordingly, thesepotholes, mud, and rocks and the like constitute obstacles to thetraveling of the unmanned vehicles 2.

Such obstacles (load) can fall at any time. There are also cases wheresuch obstacles (load) fall, but a manned vehicle 20 such as a bulldozerdiscovers and removes such obstacles. There are also times when anotherbulldozer or fuel supply truck or other manned work vehicle 20 isstopped on the travel course of the unmanned vehicle 2. In such cases,that manned vehicle 20 becomes an obstacle to the unmanned vehicle 2.And the position where such a manned vehicle 20 constituting an obstacleis stopped is also subject to change at any time. Thus the obstaclesinside the course area 68 over which the plurality of unmanned vehicles2, 2 . . . travels are not fixed. The positions thereof are subject tochange at any time as new obstacles develop in conjunction with thetraveling of the unmanned vehicles 2 or are removed.

Thus obstacles inside the course area 68 are subject to change at anytime as the work progresses.

In this embodiment aspect, a dumping area 65 is assumed as the coursearea 68 as diagrammed in FIG. 6, and a case is supposed where a travelcourse 71 is created in the dumping area 65.

As diagrammed in this FIG. 6, the dumping area 65 is an area enclosed bya boundary line 66. The dumping area 65 is provided with anentrance/exit for the unmanned vehicles 2. The entrance/exit to thedumping area. 65 and the travel course area 67 that is the travel routefor the unmanned vehicle 2 are connected.

The unmanned vehicle 2 begins traveling from a travel starting point,travels in the direction indicated by arrow A over the travel coursearea 67, and arrives at the entrance point 69 to the dumping area 65.Then it passes the entrance point 69 and enters into the dumping area 65from the dumping area entrance/exit. Then, inside the dumping area 65,the unmanned vehicle 2 reverses its direction of travel. That is, theunmanned vehicle 2 advances in the direction indicated by arrow B, andthen backs up in the direction indicated by arrow C in line with thedumping direction. The vehicle stops at the target dumping point 72 anddumps its load. That is, the dump truck 2 raises its bed and dumps theearth therein at the target dumping point 72. After completing thisdumping operation, the unmanned vehicle 2 advances in the directionindicated by arrow D, leaves the dumping area 65 from the dumping areaentrance/exit, and proceeds into the travel course area 67. The vehiclepasses the exit point 70, travels over the travel course area 67 in thedirection indicated by the arrow E, and returns to the traveltermination point. Thus the unmanned vehicle 2 is guided along thetravel course 71 described above.

Here, to indicate the actual topography outside the dumping area 65(interior enclosed by the boundary line 66) and the travel course area67, that is, outside the course area 68, that is shown here to be anarea where travel by the unmanned vehicles 2 is impossible due to suchtopography as walls and cliffs, as diagrammed in FIG. 8.

As diagrammed in FIG. 8, the position and shape of the dumping area 65are subject to change at any time as the work progresses, and theobstacles 74 inside the dumping area 65.are also subject to change atany time, wherefore the travel course 71 is revised whenever necessary,as indicated by 71′, so that vehicles can travel inside the course area68 (dumping area 65) without conflicting with obstacles 74.

FIG. 1 is a block diagram of the flow of various kinds of data in theembodiment aspect. Data are sent and received reciprocally between amonitoring station 8, unmanned vehicle 2, loading machine 14, and mannedvehicle 20. The monitoring station 8 has a function to manage andmonitor a plurality of unmanned vehicles 2, 2 . . . . A variety of dataare sent and received between the monitoring station 8, unmanned vehicle2, loading machine 14, and manned vehicle 20, whereby, not only are dataon obstacles 74 common to the plurality of unmanned vehicles 2, 2 . . .stored in a database in the monitoring station 8, but data indicatingthe position and shape of the course area 68 are also stored. The dataon the obstacles 74 are updated, and the course area 68 data areupdated, as the plurality of unmanned vehicles 2, 2 . . . travels.

The travel course 71 is revised whenever necessary to the revised travelcourse 71′ based on data which are updated whenever necessary.

FIGS. 2, 3, 4, and 5 are block diagrams of the configurations of anunmanned vehicle 20, monitoring station 8, loading machine 14, andmanned vehicle 20, respectively.

The configuration of the unmanned vehicle 2 diagrammed in FIG. 2 isdescribed first.

With a position measuring unit 33 of the unmanned vehicle 2, theposition of that vehicle (X, Y) is measured. As position measurementmeans, a gyro and wheel revolution counters provided for the front andback wheels of the unmanned vehicle 2 are used. The vehicle position ismeasured on the basis of output signals from these wheelrevolution.counters and output signals from the gyro. In this embodimentaspect, a GPS capable of measuring the position of the vehicle 2relative to the ground is also carried as a device for measuring vehiclepositions.

Deviations between the vehicle position obtained from the outputs of thewheel revolution counters and the vehicle position obtained from theoutput of the GPS that is a ground position measuring device are foundby a processor 31 in the unmanned vehicle 2. From this deviation, theroad surface condition of the road surface being-currently traveled overby the unmanned vehicle 2 is detected.

An obstacle detector 34 for detecting obstacles 74 lying ahead in thedirection of vehicle advance is carried in the unmanned vehicle 2. Amilliwave radar, laser radar, or visual sensor or the like is used asthe obstacle detector 34.

In FIG. 9 is diagrammed the way in which an obstacle 74 ahead of theunmanned vehicle 2 is detected. Let it be assumed that, as the vehicle 2is advancing in the direction indicated by arrow 75, an obstacle 74lying ahead in the direction of vehicle advance is detected by theobstacle detector 34 when a radio or laser beam is projected at aprojection angle θ. At this time, the relative position of the obstacle74 relative to the vehicle 2 is determined on the basis of the radio orlaser beam projection angle θ and the distance d to the obstacle 74 thatcorresponds to the time required for transmission and reception of theradio or laser beam. The absolute position (X, Y) of the unmannedvehicle 2 is being measured by the position measuring unit 33, whereforethe absolute position of the obstacle 74 is measured from that absoluteposition (X, Y) of the unmanned vehicle 2 and the relative position ofthe obstacle 74 relative to the vehicle 2 obtained from the obstacledetector 34.

For the obstacle detector 34, it is also permissible to use a detectorprovided with a scanning mechanism for scanning radio or laser beams.Alternatively, an obstacle detector that projects a radio or laser beamin a certain direction may also be used.

When an obstacle 74 is present in the vicinity of the unmanned vehicle2, moreover, this obstacle 74 will be discovered by an operator drivingthe loading machine 14 or manned vehicle 20. When that happens, a stopcommand is transmitted to the unmanned vehicle 2 via a communicationsunit 55 in the loading machine 14 or via a communications unit 63 in themanned vehicle 20. This stop command is received by a communicationsunit 32 in the unmanned vehicle 2.

Data indicating the vehicle position measured by that selfsame unmannedvehicle 2, data indicating the detected position of the obstacle 74,data indicating the road surface condition, and data indicating that astop command was received are processed in the processor 31 andtransmitted via the communications unit 32 to the monitoring station 8.

Data indicating the travel course 71 (or the revised travel course 71′)that that selfsame unmanned vehicle 2 should travel over are transmittedfrom the monitoring station 8, and received by the communications unit32. Data for the travel course 71 or 71′ received are also stored in atravel course memory unit 35.

In the processor 31, while continually comparing the position of thatvehicle measured by the position measuring unit 33 against successivepositions on the travel course 71 or 71′ stored in the travel coursememory unit 35, travel commands and steering commands are generated sothat the unmanned vehicle 2 arrives at the successive positions on thetravel course 71 or 71′ one after another. These travel commands andsteering commands are output to a travel mechanism unit 36 and asteering mechanism unit 37. As a result, the unmanned vehicle 2 isguided over the travel course 71 or 71′ and arrives at the targetdumping point 72.

The configuration of the loading machine 14 diagrammed in FIG. 4 isdescribed next.

In the loading machine 14 is deployed a position measuring unit 51 formeasuring the position of that vehicle, in order to measure to positionof that vehicle as the position of the obstacle 74. A GPS that canmeasure ground positions of that vehicle 14, for example, is used asposition measurement means.

From a data input unit 48 in the loading machine 14, data indicating thecourse area 68 position and shape, and data indicating the position,shape, and size of the obstacle 74 are designated and entered.

In the communications unit 55 of the loading machine, various kinds ofdata are received from the monitoring station 8, namely data on thetravel courses 71 and 71′, obstacle 74 data, course area 68 data, anddata on the positions of other vehicles.

In a display unit 50 in the loading machine 14, the course area 68,travel courses 71 and 71′, the various kinds of vehicle, including thatvehicle 14, and the obstacle(s) 74 are displayed on the same screen.

In FIG. 12(a) is given a representation of how the dumping area 65, thetravel courses 71 and 71′ inside that dumping area 65, the unmannedvehicle 2 and the manned vehicle 20 inside that dumping area 65, and theobstacle(s) 74 inside that dumping area 65 are displayed on the displayscreen 76 of the display unit 50. When the loading site is displayed,moreover, the loading area 73, travel courses 71 and 71′ inside thatloading area 73, unmanned vehicle 2 and loading machine 14 inside thatloading area 73, and the obstacle(s) 74 inside that loading area 73 willbe displayed on the display screen 76 of the display unit 50.

The relative positions of the items displayed on the display screen 76of the display unit 50 (that is, the course area 68, obstacle 74, etc.)correspond to the actual relative positions.

The position and shape of the course area 68 and the position, shape,and size of the obstacle 74 on the display screen 76 change according tothe data input from the data input unit 48 as the plurality of unmannedvehicles 2, 2 . . . travels (that is, as the operations of the vehiclesprogress). In other words, when a new instruction control input is madewith the data input unit 48, the position and shape of the course area68 and the position, shape, and size of the obstacle 74 displayed on thedisplay screen 76 of the display unit 50 change according to the contentof the instruction control inputs.

That is, the operator ascertains changes in the position and shape ofthe course area 68 visually, and also recognizes the appearance anddisappearance of obstacles 74.

Then, the operator makes data instruction control inputs using the datainput unit 48 so that the results visually ascertained on the displayscreen 76 are obtained. More specifically, the display screen 76 isconfigured with a touch panel. Data input are also automatically revisedby a data revision unit 49 as will be described subsequently.

Travel commands and steering commands are generated by the processor 47in response to the manual control inputs of the operator, and thesetravel commands and steering commands are output to a travel mechanismunit 53 and steering mechanism unit 54. As a result, the loading machine14 is steered and travels according to the manual control inputs.

The loading machine 14 also becomes the target point of the travelcourse 71 of the unmanned vehicle 2 in the loading area 73. Therefore,in the travel course revision unit 52 of the loading machine 14,processing is performed to revise the route of the travel course 71 inaccord with changes in the target point as that vehicle 14 moves.

Obstacle 74 data input and revised at the loading machine 14, coursearea 68 data input and revised, travel course 71 data revised, and dataindicating the position of that vehicle 14 that was measured areprocessed by the processor 47 and transmitted to the monitoring station8 via the communications unit 55. When the travel course 71 has beenrevised in conjunction with movements of the loading machine 14, dataindicating utilization permission to the effect that permission totravel on that revised travel course 71 is granted are transmitted tothe monitoring station 8.

When the operator of the loading machine 14 has discovered visually thatan obstacle 74 is present in the vicinity of the traveling unmannedvehicle 2, a stop command is transmitted via the communications unit 55to that unmanned vehicle 2 to tell it to stop.

The configuration of the unmanned vehicle 20 diagrammed in FIG. 5 isnext described.

In FIG. 5, items designated by the same symbol as in FIG. 4 areidentical configuring elements. In other words, the manned vehicle 2 isconfigured more or less the same way as the loading machine 14. Thepoint of difference is that, whereas in the loading machine 14 there isa travel course revision unit 52, the manned vehicle 20 has no suchtravel course revision unit 52.

The configuration of the monitoring station 8 diagrammed in FIG. 3 isnext described.

In FIG. 3, items designated by the same symbol as in FIG. 4 areidentical configuring elements. In other words, the same displays aremade on the display unit 50 of the monitoring station 8 as on thedisplay screen 76 diagrammed in FIG. 12(a). Accordingly, when anoperator of the monitoring station 8 designates and enters obstacle 74data and course area 68 data from the data input unit 48, the contentdisplayed on the display screen 76 changes according to the contententered. The input data are also automatically revised by the datarevision unit 49.

Various kinds of data transmitted from the plurality of unmannedvehicles 2, 2 . . . , the loading machine 14, and the manned vehicle 20are received by the communications unit 45 in the monitoring station 8.These various kinds of data are processed by the processor 38.

More specifically, the position data for the plurality of unmannedvehicles 2, 2 . . . , the loading machine 14, and the manned vehicle 20,which is to say the position data for all of the vehicles, are stored inthe vehicle position memory unit 46. The content so stored are rewrittento the latest position data every time the latest position data aretransmitted.

In a course area memory unit 40 are stored course area 68 datatransmitted from the loading machine 14, course area 68 data transmittedfrom the manned vehicle 20, and course area 68 data input and revised atthe monitoring station 8. The content so stored is rewritten to thelatest data every time the latest course area 68 data are transmitted.That is, in the course area memory unit 40 are stored the latestposition and shape data for the course area 68 which are subject tochange at any time as the work progresses.

In the processor 38 of the monitoring station 8, data are generatedwhich indicate the position, shape, and size of an obstacle 74, asdescribed subsequently, based on obstacle position data, road surfacecondition data, stop command reception data, and vehicle position datatransmitted from the unmanned vehicle 2.

In the processor 38 of the monitoring station 8, similarly, data aregenerated which indicate the position, shape, and size of an obstacle74, as described subsequently, based on obstacle data and vehicleposition data transmitted from the loading machine 14.

In the processor 38 of the monitoring station 8, similarly, data aregenerated which indicate the position, shape, and size of an obstacle74, as described subsequently, based on obstacle data and vehicleposition data transmitted from the manned vehicle 20.

In the obstacle memory unit 41 are stored the obstacle 74 data generatedon the basis of the data transmitted from the unmanned vehicle 2,loading machine 14, and manned vehicle 20, and obstacle 74 data inputand revised at the monitoring station 8. The content so stored isrewritten to the latest data every time data are generated for thelatest obstacle of obstacles 74. In other words, in the obstacle memoryunit 41 are stored data on the latest position, shape, and size ofobstacles 74 that are subject to change at any time as the workprogresses.

On the display screen 76 of the display unit 50, the latest vehicleposition, the latest course area 68 (dumping area 65) position andshape, and the latest obstacle 74 position, shape, and size aredisplayed based on the content of memory in the vehicle position memoryunit 46, content of memory in the course area memory unit 40 and contentof memory in the obstacle memory unit 41 (cf. FIG. 12(a)).

Before the unmanned vehicle 2 begins to operate, a manned vehicle 20used for teaching travels beforehand over the course area 68, whereuponposition data on the course area 68 (dumping area 65) are acquired, andposition data on the travel course 71 of the unmanned vehicle 2 areacquired. The position data obtained from this teaching are sent to themonitoring station 8. These position data may also be acquired bysurveying.

In the travel course generator 44 of the monitoring station 8 isgenerated the travel course 71, based at first on the position dataobtained by the teaching described above.

Then, as the multiple unmanned vehicles 2, 2 . . . travel (as the workprogresses), data stored in the course area memory unit 40 and obstaclememory unit 41 are read out whenever necessary. Based on the latestobstacle and course area data read out whenever necessary, the travelcourse 71 is revised so that the unmanned vehicles 2 travel within thecourse area 68 (dumping area 65) and pass the target dumping point 72without conflicting with the obstacle or obstacles 74.

The position data for the travel course 71 generated by the travelcourse generator 44 or the position data for the revised travel course71′ revised are transmitted to the unmanned vehicles 2 through thecommunications unit 45.

Next, various aspects are described for revising the travel course 71 inresponse to the appearance or disappearance at any time of an obstacle74.

Aspect 1

Let it be assumed that, as diagrammed in FIG. 12(a), a dumping area 65,a travel course 71 within that dumping area 65, and an unmanned vehicle2 and manned vehicle 20 within that dumping area 65 are displayed on thedisplay screen 76 of the display unit 50 in the manned vehicle 20.

The operator visually ascertains the appearance and disappearance ofobstacles 74 in the course area 68. An example of this would be whenrock that is part of the load of the unmanned vehicle 2 falls to theroad surface within the field of view of the operator. Other examplesthereof include the formation of potholes or mud on the road surface, orrough road surface, within the field of view of the operator. Suchpotholes, mud, and rough road surface constitute obstacles that cannotbe detected by the obstacle detector 34 carried on the unmannedvehicles.

Another such case would be when fallen load (rock) is removed by anmanned vehicle 20 such as a bulldozer within the field of view of theoperator.

Next, the operator shifts his or her attention to the display screen 76,and changes the position of the appearance or disappearance of theobstacle 74 within the actual dumping area 65 to a position on thedisplay screen 76. In other words, the dumping area 65 is displayed onthe display screen 76, wherefore the position of the appearance ordisappearance of the obstacle 74 can be confirmed on the screen from therelative positional relationship with that dumping area 65, and thatposition can be designated.

When an obstacle 74 newly appears, for example, data on the position ofthat appearance and on the shape and size are designated and input fromthe data input unit 48. Thus, as diagrammed in FIG. 12(a), the obstacle74 ascertained by the operator will be displayed on the display screen76.

Processing similar to the obstacle designation processing describedabove, performed through the display unit 50 and the data input unit 48of the manned vehicle 20, is performed through the display unit 50 andthe data input unit 48 of the loading machine 14. And a similar obstacledesignation process is also performed in the monitoring station 8.

In the obstacle memory unit 41 of the monitoring station 8 are storeddata on the position, shape, and size of obstacles 74 designated on thedisplay screen 76 of the display unit 50. And the content stored in theobstacle memory unit 41 is updated every time an obstacle 74 is newlydesignated on the display screen 76.

Then, in the travel course generator 44 of the monitoring station 8, therevised travel course 71′ that avoids that obstacle 74 is generated onthe basis of data on the obstacle 74 stored in the obstacle memory unit41, as indicated by the broken line in FIG. 12(a). The display screen 76displays a travel course 71′ which has been revised.

The revised travel course 71′ at the actual work site is diagrammed inFIG. 8.

The unmanned vehicle 2 is guided over that revised travel course 71′.Thus the unmanned vehicle 2 can travel safely without conflicting withthe obstacle 74.

When the disappearance of the obstacle 74 is indicated on the displayscreen 76, no conflict will occur even if the unmanned vehicle 2 passesover the position of that disappearance. Thereupon, in the travel coursegenerator 44, the generation of a travel course that passes over theobstacle disappearance position is enabled. That is, unnecessaryrevision of the travel course is prevented.

In this embodiment aspect, the processing for revising the travel course71 in response to indications of the appearance and disappearance ofobstacles 74 on the display screen 76 is performed by the monitoringstation 8, but provision may also be made so that the revision of thetravel course 71 is performed by the loading machine 14. Embodiments arealso possible that have the manned vehicle 20 perform the sameprocessing.

Based on this embodiment aspect, as described above, the obstacle 74indicated on the display screen 76 is stored as the position of anobstacle 74 common to the plurality of unmanned vehicles 2, 2 . . . . Asa consequence, it is possible to perform the operation of revisingtravel courses 71, 71 . . . for those unmanned vehicles 2, 2 . . .easily and in a short time from those stored data. Hence revisionoperations on the travel courses 71, 71 . . . can be performed with goodwork efficiency. Work efficiency improves dramatically compared toteaching operations wherewith a teaching vehicle must be driven everytime an obstacle develops.

Also, by having the indications on the display screen 76 made whenevernecessary, the obstacle 74 data are updated whenever necessary,wherefore a work site where the appearance and disappearance ofobstacles 74 occur in real time, such as one where a plurality ofunmanned vehicles 2, 2 . . . is traveling, can be coped with. In otherwords, obstacles 74 that change at odd times are not overlooked, nor arethings erroneously judged to be obstacles.

Based on this embodiment aspect, moreover, provision is made so that anoperator visually verifies that something is an obstacle 74, whereforeeven obstacles 74 that exist within a range that is undetectable by theobstacle detector 34 carried on board an unmanned vehicle or obstacles74 having undetectable shapes (such as potholes, mud, or rough roadsurface and the like) can be judged to be obstacles.

Based on this embodiment aspect, furthermore, provision is made so thatan operator visually verifies that something is an obstacle 74,wherefore obstacles 74 can be ascertained without fail, irrespective ofthe surrounding environment, compared to cases where detection is madeby an obstacle detector 34.

Aspect 2

Let it here be assumed that, as diagrammed in FIG. 12(a), a dumping area65 and an unmanned vehicle 2 and manned vehicle 20 inside that dumpingarea 65 are displayed on the display screen 76 of the display unit 50 ofthe manned vehicle 20. On that display screen 76 is also displayed acompleted travel course 71″ that has already been traveled over by theunmanned vehicle 2, as diagrammed in FIG. 12(b).

For this run-completed travel course 71″, the latest travel course canbe selected from the travel courses that have already been completelytraveled over in the past. Or the run-completed travel course 71″ can beselected and displayed on the screen by designating a symbol (vehiclenumber) that specifies an unmanned vehicle 2.

The operator visually ascertains the development of obstacles 74 withinthe course area 68. When it is ascertained that rock is present on theroad surface within the field of view of the operator, the operatorshifts his or her attention to the display screen 76 and changes theposition where the obstacle 74 (rock) appeared in the actual dumpingarea 65 to the position on the display screen 76.

In such case, the dumping area 65 is displayed on the display screen 76,wherefore the position where that obstacle 74 appeared can be judged byits relative positional relationship with the dumping area 65.

At work sites at mining sites of extensive area, obstacles 74 such asrock and the like occur mainly from load carried on the unmannedvehicles 2 being dropped. Accordingly, such obstacles 74 are most oftenpositioned on a run-completed travel course 71″ that an unmanned vehicle2 has traveled over.

Here, as diagrammed in FIG. 12(b), the run-completed travel course 71″is being displayed on the display screen 76, wherefore the positionwhere such an obstacle 74 as rock or the like developed can be judgedeven more accurately by the relative positional relationship thereofwith that run-completed travel course 71″. In other words, the operatorcan revise a judgment concerning an obstacle 74 judged by the relativepositional relationship with the course area 68 to one wherein it ispositioned at 74′ on the run-completed travel course 71″, and designateand input accurate position data on the obstacle 74 from the data inputunit 48. The directions in which load falls will differ depending on thecurvature of the travel course 71″, etc. That being so, the position ofthe obstacle 74 can be revised even more precisely taking the directionin which the load falls (i.e. behind the vehicle, to the left side ofthe vehicle, or to the right side of the vehicle) into consideration.

Thus, based on this embodiment aspect, a benefit is realized in that theposition of an obstacle 74 occurring due to load such as rock or thelike falling from an unmanned vehicle 2 can be indicated even moreaccurately on the display screen 76.

The same processing as the obstacle designation processing describedabove and done through the display unit 50 and the data input unit 48 ofthe manned vehicle 20 is also done through the display unit 50 and thedata input unit 48 of the loading machine 14. Or the same obstacledesignation processing is done at the monitoring station 8 also.

The processing following the obstacle designation processing is the sameas in aspect 1, wherefore no description thereof is given here.

Aspect 3

Let it here be assumed that, as diagrammed in FIG. 12(a), a dumping area65 and an unmanned vehicle 2 and manned vehicle 20 inside that dumpingarea 65 are displayed on the display screen 76 of the display unit 50 ofthe manned vehicle 20. On that display screen 76 is also displayed acompleted travel course 71″ that has already been traveled over by theunmanned vehicle 2, as diagrammed in FIG. 12(b).

The operator visually ascertains the development of obstacles 74 withinthe course area 68. When it is ascertained that rock is present on theroad surface within the field of view of the operator, the operatorshifts his or her attention to the display screen 76 and changes theposition where the obstacle 74 (rock) appeared in the actual dumpingarea 65 to the position on the display screen 76.

In such case, the dumping area 65 is being displayed on the displayscreen 76, wherefore the position where that obstacle 74 appeared can bejudged from its relative positional relationship with the dumping area65. Thereupon, the operator designates and inputs data on the positionof the obstacle 74 judged in this way from the data input unit 48.

At work sites at mining sites of extensive area, obstacles 74 such asrock and the like occur mainly from load carried on the unmannedvehicles 2 being dropped. Accordingly, such obstacles 74 are most oftenpositioned on a run-completed travel course 71″ that an unmanned vehicle2 has traveled over.

Thereupon, in the data revision unit 49, based on the position data onthe run-completed travel course 71″, as diagrammed in FIG. 12(b),revising processing is automatically performed to reposition theposition of the obstacle 74 designated by the operator to 74′ on therun-completed travel course 71″. The direction in which load falls willdiffer depending on the curvature of the travel course 71″, etc. Thatbeing so, the position of the obstacle 74 may be revised more preciselybased on data indicating the direction in which the load falls (i.e.behind the vehicle, to the left side of the vehicle, or to the rightside of the vehicle) into consideration.

Based on this embodiment aspect, as provided for in the foregoing, abenefit is realized in that, when an obstacle 74 occurring due to loadsuch as rock or the like falling from an unmanned vehicle 2 isdesignated and input on the display screen 76, that indicated positionis automatically revised to the more accurate position 74′.

The same processing as the obstacle designation revision processingdescribed above and done through the display unit 50, the data inputunit 48, and the data revision unit 49 of the manned vehicle 20 is alsodone through the display unit 50, data input unit 48, and data revisionunit 49 of the loading machine 14. Or the same obstacle designationrevision processing is done at the monitoring station 8 also.

The processing following the obstacle designation revision processing isthe same as in aspect 1, wherefore no description thereof is given here.

Aspect 4

As diagrammed in FIG. 9, obstacles 74 ahead of an unmanned vehicle 2 aredetected by an obstacle detector 34 in that vehicle. Obstacles 74 to theside or behind the unmanned vehicle 2 may also be detected by suitablyaltering the numbers of obstacle detectors 34 deployed and the positionswhere they are deployed. Obstacle detectors 34 may also be carried inthe manned work vehicles 20 and 14. And obstacle detectors 34 may beeither carried in all of the unmanned vehicles or in only some of theunmanned vehicles.

In the processor 31 of the unmanned vehicle 2, the relative position ofthe obstacle 74 relative to the unmanned vehicle 2 is computed, based onthe projection angle e of the radio or laser beam projected from theobstacle detector 34 and on the distance d to the obstacle 74corresponding to the transmission-receive time for the radio or laserbeam. In the processor 31 of the unmanned vehicle 2, furthermore, theabsolute position of the obstacle 74 is computed by adding the absoluteposition (X, Y) of the vehicle 2 measured by the position measuring unit33 when the obstacle 74 was detected by the obstacle detector 34 and therelative position of the obstacle 74 found from the projection distanced and projection angle θ described above.

The processing for computing the position of the obstacle 74 may also beperformed at the monitoring station 8 by transmitting the detectionsignals of the obstacle detector 34 to the monitoring station 8.

For this reason, computed positional data for obstacles 74 transmittedfrom the plurality of unmanned vehicles 2, 2 . . . will be stored in theobstacle memory unit 41 of the monitoring station 8. The content storedin this obstacle memory unit 41 will be updated every time anotherobstacle 74 is detected by the obstacle detector 34 and the position ofthat obstacle 74 is computed. There will be times, however, when thesame obstacle 74 is detected by a plurality of the unmanned vehicles 2,2 . . . . In such cases, the average value of the positions computed forthat same obstacle 74 transmitted from the vehicles 2, 2 . . . can befound, and that average value stored in the obstacle memory unit 41 asthe position data for that same obstacle 74.

In the travel course generator 44 of the monitoring station 8, a revisedtravel course 71′ that avoids the obstacle 74 is generated, based on theposition data for the obstacle 74 stored in the obstacle memory unit 41,as indicated by the broken line in FIG. 12(a). The revised travel course71′ is then displayed on the display screen 76.

The revised travel course 71′ in the actual work site is diagrammed inFIG. 8.

The unmanned vehicle 2 is guided over that revised travel course 71′.Thus the unmanned vehicle 2 can travel safely without conflicting withthe obstacle 74.

Based on this embodiment aspect, as described above, an obstacle 74detected by one unmanned vehicle 2 is stored as the position of anobstacle 74 common to the plurality of unmanned vehicles 2, 2 . . . ,wherefore the operation of revising the travel courses 71, 71 . . . ofthat plurality of unmanned vehicles 2, 2 . . . can be performed easilyand in a short time by using those stored data. Thus the work forrevising travel courses 71, 71 . . . can be performed efficiently.

Moreover, because an obstacle 74 detected by one unmanned vehicle 2 isconsidered an obstacle 74 also for the other unmanned vehicles 2, theother unmanned vehicles 2 can avoid that obstacle 74 without fail, evenif that obstacle 74 is not detected by the obstacle detectors 34 carriedon board those other unmanned vehicles 2. In other words, even in caseswhere the obstacle detector 34 of another unmanned vehicle 2malfunctions or its operation becomes uncertain, or cases where anobstacle 74 cannot be detected precisely due to the influence of thesurrounding environment, that other vehicle 2 can still avoid theobstacle 74 without fail.

Based on this embodiment aspect, furthermore, the detection andcomputation of an obstacle 74 by the plurality of unmanned vehicles 2, 2. . . are performed whenever necessary, and the data on the obstacle 74is updated as necessary, wherefore a work site where obstacles 74develop in real time, such as a work site where a plurality of vehicles2, 2 . . . travels about, can be coped with. That is, by mutuallysharing data obtained from the plurality of unmanned vehicles, obstacles74 that are subject to change at any time will not be overlooked.

Aspect 5

In the processor 31 of the unmanned vehicle 2, the deviation between thevehicle position obtained from the output of the wheel revolutioncounter and the vehicle position obtained from the output of the GPSthat is a ground position measurement system is found, and the roadsurface condition of the road surface over which that unmanned vehicle 2is currently traveling is detected from that deviation.

The road surface condition data are transmitted to the monitoringstation 8, and a judgment is made by the processor 38 in the monitoringstation 8 as to whether or not that road surface constitutes an obstacle74.

That is, when the deviation between the vehicle position obtained fromthe output of the wheel revolution counter and the vehicle positionobtained from the output of the GPS that is a ground positionmeasurement system is equal to or greater than a prescribed thresholdvalue (that is, when there is little change in the ground position eventhough the wheels are turning), it is judged that the unmanned vehicle 2is slipping badly, and that the road surface at that time constitutes anobstacle 74 (mud or pothole or the like). It is further judged that thecurrent measured position (X, Y) of the unmanned vehicle 2 thattransmitted those road surface condition data is the position of theobstacle 74 (mud, pothole, etc.). The size of the obstacle 74 (mud,pothole, etc.) may also be established according to how badly theslipping is (how large the deviation noted above is).

A judgment is made as to whether or not an obstacle 74 exists from thedeviation between the vehicle position obtained from the output of thewheel revolution counter and the vehicle position obtained from theoutput of the GPS that is a ground position measurement system. However,a judgment as to whether or not an obstacle 74 exists may also be madefrom the deviation between the output of a front wheel revolutioncounter and the output of a back wheel revolution counter. When thedeviation between the number of revolutions of the front wheels and thenumber of revolutions of the back wheels is large, it can be judged thatthe unmanned vehicle 2 is slipping.

That an obstacle 74 exists is judged by detecting that slipping hasoccurred, moreover, but the existence of an obstacle 74 may also bejudged by detecting road surface roughness.

On board the unmanned vehicle 2 is carried a gyro as a componentconfiguring the position measuring unit 33. The output from that gyro,that is, the angular velocity of the angle of attitude of the unmannedvehicle 2, is transmitted as road surface condition data to themonitoring station.8.

At the monitoring station 8, when the angular velocity of the angle ofattitude of the unmanned vehicle 2 output from the gyro is equal to orgreater than a prescribed threshold value (that is, when the change inattitude per unit time about the yaw axis of the unmanned vehicle 2 islarge), it is judged that the road surface under the unmanned vehicle 2is very rough, and that the road surface at that time constitutes anobstacle 74 (road surface roughness). Then it is judged that the currentmeasured position (X, Y) of the unmanned vehicle 2 that transmitted theroad surface condition data is the position of an obstacle 74 (roadsurface roughness). The size of the obstacle 74 (road surface roughness)may also be established according to the size of the road surfaceroughness (that is, according to the size of the values output by thegyro).

The judgment as to whether or not an obstacle 74 is constituted is madefrom the output of the gyro, but an inclinometer may be carried on boardthe unmanned vehicle 2, and the judgment as to whether or not anobstacle 74 is constituted made on the basis of the rate of change inthe angle of inclination per unit time obtained from the output of thatinclinometer. When the rate of change in the angle of inclination perunit time obtained from the output of the inclinometer is large (thatis, when the change in attitude per unit time about the roll or pitchaxis of the unmanned vehicle 2 is large), it can be judged that the roadsurface under the unmanned vehicle 2 is rough.

Even in cases where the degree of slip or road surface roughness asdescribed in the foregoing is too small to be judged as constituting anobstacle 74, depending on that degree of slip or road surface roughness,a travel command or stop command can be transmitted to the unmannedvehicle 2. That is, the monitoring station 8 can transmit a travelcommand to the unmanned vehicle 2 to cause it to lower its speedaccording to the extent of the slip or road surface roughness. Dependingon the case, moreover, the monitoring station 8 may transmit a stopcommand to the unmanned vehicle 2 to cause it to stop traveling.

In this embodiment aspect, furthermore, the degree of slip or roadsurface roughness is judged on the monitoring station 8 side on thebasis of road surface condition data, but judgments of the degree ofslip or road surface roughness may also be made independently on theunmanned vehicle 2 side on the bases of the road surface condition data.

In that case, when it is judged on the unmanned vehicle 2 side thatthere is slipping or that the road surface is rough, that unmannedvehicle 2 lowers its speed of travel according to the level of slip orroad surface roughness. If the slip or road surface roughness equals orexceeds a prescribed threshold value, travel is stopped. In that case,data are transmitted to the monitoring station 8 indicating that theunmanned vehicle 2 has lowered its speed or stopped traveling.

It is also permissible to have judgments as to whether or not anobstacle 74 is constituted made in the unmanned vehicle 2, and theresults of that judgment transmitted to the monitoring station 8. Inthat case, the monitoring station 8 may use the judgment resultstransmitted from the unmanned vehicle 2 as they are, or, alternatively,a final decision as to whether or not an obstacle 74 is constituted maybe made at the monitoring station 8 after further analysis of the datatransmitted from the unmanned vehicle 2 (i.e. the road surface conditiondata, speed lowered or travel stopped data, and obstacle judgment data).

For that reason, in the obstacle memory unit 41 of the monitoringstation 8, the measured position (X, Y) of the unmanned vehicle 2 at thetime the slip or road surface roughness occurred is stored in memory asthe position of the obstacle 74. The content stored in the obstaclememory unit 41 is updated every time a judgment is made by the obstacledetector 34 that a new obstacle 74 (slip or road surface roughness)exists.

In the travel course generator 44 of the monitoring station 8, a revisedtravel course 71′ that avoids the obstacle 74 is generated, based on theposition data for the obstacle 74 stored in the obstacle memory unit 41,as indicated by the broken line in FIG. 12(a). The revised travel course71′ is then displayed on the display screen 76.

The revised travel course 71′ in the actual work site is diagrammed inFIG. 8.

The unmanned vehicle 2 is guided over that revised travel course 71′.Thus the unmanned vehicle 2 can travel safely without conflicting withthe obstacle 74.

Based on this embodiment aspect, as described above, an obstacle 74(slip or road surface roughness) that has occurred at one unmannedvehicle 2 is stored as the position of an obstacle 74 common to theplurality of unmanned vehicles 2, 2 . . . , wherefore the operation ofrevising the travel courses 71, 71 . . . of that plurality of unmannedvehicles 2, 2 . . . can be performed easily and in a short time fromthose stored data.

Based on this embodiment aspect, moreover, data on the obstacle 74 areupdated as necessary, according to the occurrence at odd times ofobstacles 74 (slips or road surface roughness), by the plurality ofunmanned vehicles 2, 2 . . . , wherefore a work site where obstacles 74develop in real time, such as a work site where a plurality of vehicles2, 2 . . . travels about, can be coped with. That is, by mutuallysharing obstacle data obtained from the plurality of unmanned vehicles,obstacles 74 (slips and road surface roughness) that are subject tochange at any time will not be overlooked.

Based on this embodiment aspect, furthermore, because judgements aremade that an obstacle 74 exists from the condition of the road surfacetraveled over by the unmanned vehicles 2, even obstacles (such as mud,potholes, and roughness or the like) that cannot be detected by theobstacle detector 34 carried on board the unmanned vehicles can bejudged to be obstacles.

There will also be cases where such obstacles 74 as mud, potholes, orrough road surfaces fluidly change or disappear as the work progresses.When an operator visually determines that an obstacle 74 hasdisappeared, he or she indicates the disappearance of that obstacle 74on the display screen 76 as described earlier.

At the monitoring station 8, processing is done to erase data on thecorresponding obstacle 74 from the obstacle memory unit 41 in responseto such indications of the disappearance of an obstacle 74.

Provision may also be made so that after a certain time has elapsedsince an obstacle 74 was stored in the obstacle memory unit 41 a queryis sent from the monitoring station 8 to an operator asking whether thatobstacle 74 has disappeared or not.

In this embodiment aspect, moreover, it is assumed that all of theunmanned n vehicles detect road surface conditions, but it ispermissible to have only some of the unmanned vehicles detect the roadsurface conditions. The road surface conditions may also be detected bythe loading machine 14 and manned vehicle 20. In such cases, obstacles74 (mud, potholes, rough road surfaces and the like) on the road surfacetraveled over by the loading machine 14 and manned vehicle 20 can beascertained.

Aspect 6

When the operator of the manned vehicle 20 or loading machine 14discovers visually that an obstacle 74 exists in the vicinity of atraveling unmanned vehicle 2, he or she transmits a stop command via thecommunications unit 55 to that unmanned vehicle 2 instructing it tostop. In such cases, the obstacle 74 would be load (rock or earth, etc.)fallen from an unmanned vehicle 2, mud, a pothole, or rough road surfaceor the like.

At the monitoring station 8, data are received from the unmanned vehicle2 receiving the stop command notifying that such stop command wasreceived. At the monitoring station 8, furthermore, data on the currentmeasured position (X, Y) of the unmanned vehicle 2 that received thatstop command are received. Thereupon, at the monitoring station 8, ajudgment can be made that the measured position (X, Y) of the unmannedvehicle 2 that received that stop command (i.e. the position where theunmanned vehicle 2 stopped) is the position of the obstacle 74.

In order to define the position of the obstacle 74 more accurately, dataindicating the relative position of the obstacle 74 relative to theunmanned vehicle 2 may be transmitted to the monitoring station 8 fromthe loading machine 14 or manned vehicle 20 that transmitted that stopcommand.

In FIG. 10 and FIG. 11, respectively, are diagrammed examples ofpositional relationships between an obstacle 74 and a travel course.

When, as diagrammed in FIG. 10, the operator of an manned vehicle 20 orloading machine 14 verifies that an obstacle 74 exists behind anunmanned vehicle 2 (on the travel course 71), he or she transmitscoordinate position data in a coordinate system X-Y having that unmannedvehicle 2 as the origin to the monitoring station 8. Or the data “L(m)behind unmanned vehicle 2” may be transmitted to the monitoring station8. In that case, the corresponding data are transmitted to themonitoring station 8 when the corresponding position is indicated on thedisplay screen 76 of the display unit 50 of the manned vehicle 20 orloading machine 14.

At the monitoring station 8, the position of the obstacle 74 isaccurately computed based on the measured position (X, Y) of theunmanned vehicle 2 that received the stop command (i.e. the positionwhere the unmanned vehicle 2 stopped) and the relative position datatransmitted from the manned vehicle 20 or loading machine 14. That is,the accurate position of the obstacle 74 is specified as being behindthe unmanned vehicle 2 (on the travel course 71).

Similarly, when, as diagrammed in FIG. 11, the operator of the mannedvehicle 20 or loading machine 14 verifies that an obstacle 74 exists atone side of an unmanned vehicle 2, he or she transmits coordinateposition data in a coordinate system X-Y having that unmanned vehicle 2as the origin to the monitoring station 8. Or the data “L(m) to side ofunmanned vehicle 2” may be transmitted to the monitoring station 8. Inthat case, the corresponding data are transmitted to the monitoringstation 8 when the corresponding position is indicated on the displayscreen 76 of the display unit 50 of the manned vehicle 20 or loadingmachine 14.

At the monitoring station 8, the position of the obstacle 74 isaccurately computed based on the measured position (X, Y) of theunmanned vehicle 2 that received the stop command (i.e. the positionwhere the unmanned vehicle 2 stopped) and the relative position datatransmitted from the manned vehicle 20 or loading machine 14. That is,the accurate position of the obstacle 74 is specified as being to oneside of the unmanned vehicle 2.

The shape and size of the obstacle 74 may also be specified, as well asthe position thereof, by transmitting data on the shape and size of theobstacle 74 to the monitoring station 8 from the manned vehicle 20 orloading machine 14.

Thus the position of the unmanned vehicle 2 that received the stopcommand (or a position close to one side thereof) is stored in theobstacle memory unit 41 of the monitoring station 8 as the position ofthe obstacle 74. And the content stored in the obstacle memory unit 41is updated every time an unmanned vehicle 2 receives a stop command.

In the travel course generator 44 of the monitoring station 8, a revisedtravel course 71′ that avoids the obstacle 74 is generated, based on theposition data for the obstacle 74 stored in the obstacle memory unit 41,as indicated by the broken line in FIG. 12(a). The revised travel course71′ is then displayed on the display screen 76.

The revised travel course 71′ in the actual work site is diagrammed inFIG. 8.

The unmanned vehicle 2 is guided over that revised travel course 71′.Thus the unmanned vehicle 2 can travel safely without conflicting withthe obstacle 74.

Based on this embodiment aspect, as described in the foregoing, thelocation where one unmanned vehicle 2 has stopped is stored in memory asthe position of an obstacle 74 common to the plurality of unmannedvehicles 2,2 . . . . Therefore, from these stored data, the operation ofrevising the travel courses 71, 71 . . . for the plurality of unmannedvehicles 2, 2 . . . can be done easily and in a short time. Thus theoperation of revising the travel courses 71, 71 . . . can be performedwith good work efficiency.

Based on this embodiment aspect, furthermore, the data on the obstacle74 are updated as necessary, in response to the plurality of unmannedvehicles 2, 2 . . . stopping at odd times, wherefore a work site whereobstacles 74 develop in real time, such as a work site where a pluralityof vehicles 2, 2 . . . travel about, can be coped with. That is, bymutually sharing obstacle data obtained from the plurality of unmannedvehicles, obstacles 74 that are subject to change at any time will notbe overlooked.

Based on this embodiment aspect, furthermore, an operator verifiesobstacles 74 visually, wherefore even obstacles 74 that cannot bedetected by the obstacle detector 34 carried on board the unmannedvehicles (such as mud, potholes, or rough road surface, etc.) can bejudged to be an obstacle.

Based on this embodiment aspect, moreover, the verification thatsomething constitutes an obstacle 74 is done visually by an operator,wherefore, compared to when detection is made by an obstacle detector34, an obstacle 74 can be definitely ascertained irrespective of thesurrounding environment.

In this embodiment aspect, it is assumed that all of the unmannedvehicles have functions for receiving stop commands and then stopping,but embodiment is also possible such that the functions for receivingstop commands and then stopping are imparted only to some of theunmanned vehicles.

Aspect 7

With the position measuring units 51 in the manned vehicle 20 andloading machine 14, the position of that selfsame vehicle is measured.These measured position data are transmitted to the monitoring station8.

The manned vehicle 20 and loading machine 14 become obstacles to thetraveling of the plurality of vehicles 2, 2 . . . .

That being so, the measured positions transmitted from the mannedvehicle 20 and loading machine 14 are stored as the positions ofobstacles 74 in the obstacle memory unit 41 in the monitoring station 8.The content stored in the obstacle memory unit 41 is updated every timethe measured position of the manned vehicle 20 or loading machine 14 isupdated, which may happen anytime.

In the travel course generator 44 of the monitoring station 8, a revisedtravel course 71′ that avoids an obstacle 74 is generated on the basisof position data for that obstacle 74 stored in the obstacle memory unit41, as indicated by the broken line in FIG. 12(a). The revised travelcourse 71′ is displayed on the display screen 76.

The revised travel course 71′ at the actual work site is diagrammed inFIG. 8.

The unmanned vehicle 2 is guided over that revised travel course 71′.Thus the unmanned vehicle 2 can travel safely without conflicting withthe obstacle 74.

Provision may also be made so that the revision of the stored positionof the obstacle 74 is performed at odd times, irrespective of whetherthe manned vehicle 20 and loading machine 14 are traveling or stopped.

Alternatively, provision may be made so that the updating of the storedposition of the obstacle 74 is only performed each time the mannedvehicle 20 or loading machine 14 stops, and not while they aretraveling. In that case, while the manned vehicle 20 and loading machine14 are traveling, the obstacle data corresponding to those travelingvehicles will be erased from the content stored in the obstacle memoryunit 41.

However, if the stored positions of obstacles 74 are updated at oddtimes while the manned vehicle 20 and loading machine 14 are traveling,the travel course 71 will be revised frequently. In order to avoid that,it is preferable that the stored positions of the obstacles 74 beupdated, and the travel course 71 revised, every time the manned vehicle20 or loading machine 14 stops.

Also, even though the travel course 71 has been revised to avoid themanned vehicle 20 and loading machine 14, there is still a danger ofconflicting with the unmanned vehicle 2 when the manned vehicle 20 andloading machine 14 resume traveling. That being the case, it ispreferable that radio communications be conducted reciprocally betweenthe unmanned vehicle 2, on the one hand, and the manned vehicle 20 andloading machine 14, on the other, and the unmanned vehicle 2 guidedwhile verifying the mutual positional relationships.

In this embodiment aspect, the case where the unmanned vehicle 20 andloading machine 14 themselves become obstacles 74 is assumed, but thefollowing embodiment is also possible.

That is, when an operator discovers an obstacle 74 such as rock or thelike, the manned vehicle 20 is made to continue traveling up to aposition near that obstacle 74. Thereupon, the manned vehicle 20specifies the relative position of the obstacle 74, relative to thatselfsame vehicle, as diagrammed in FIG. 10 and FIG. 11. These relativeposition data are transmitted to the monitoring station 8.

At the monitoring station 8, the position of the obstacle 74 isaccurately computed on the basis of the measured position data for themanned vehicle 20 transmitted and the relative position data for theobstacle 74, relative to the manned vehicle 20. These position data forthe obstacle 74 are stored in the obstacle memory unit 41.

In this embodiment aspect, only the position data for the obstacle 74are transmitted to the monitoring station 8, but embodiment is alsopossible such that data on the shape and size of the obstacle 74 aregenerated and transmitted to the monitoring station 8.

In that case, the vehicle travel speed and direction of vehicle advanceare computed on the basis of the output of the position measuring unit51 in the manned vehicle 20 and loading machine 14. Then data on thesize of the obstacle 74 are generated according to the size of thatcomputed vehicle speed. More specifically, by judging the obstacle 74 tobe successively larger as the travel speeds of the manned vehicle 20 andloading machine 14 are progressively higher, the size of the obstacle 74is specified.

Shape data for the obstacle 74 are also generated according to thedirection of vehicle advance computed as noted above. More specifically,by judging the obstacle 74 to have a shape that is long in the directionof the advance of the manned vehicle 20 and loading machine 14, theshape of the obstacle 74 is specified.

Thus position, shape, and size data for.the obstacle 74 are stored inthe obstacle memory unit 41.

In this embodiment aspect, it is assumed that the manned work vehicles20 and 14 constitute obstacles to the unmanned vehicle 2, but those workvehicles 20 and 14 may also be unmanned vehicles.

According to this embodiment aspect, as described in the foregoing, thework vehicles 20 and 14 are stored as positions of obstacles 74 commonto the plurality of vehicles 2, 2 . . . , wherefore it is possible toperform the operation of revising the travel courses 71, 71 . . . forthe plurality of vehicles 2, 2 . . . easily and in a short time fromthose data stored in memory. Hence the operation of revising the travelcourses 71, 71 . . . can be done with good work efficiency.

The obstacle 74 data are updated as necessary as the positions of thework vehicles 20 and 14 are altered at odd times, wherefore work siteswhere obstacles 74 change in real time, such as work sites where aplurality of vehicles 2, 2 . . . is traveling about, can be coped with.That is, obstacles 74 that are subject to change at any time are nolonger overlooked.

In the embodiment aspect(s) described in the foregoing, cases whererevised travel courses 71′ are generated according to obstacle 74 dataare assumed. However, with this invention it is not absolutely necessaryto generate a travel course. It is only required that at least obstacle74 data are acquired. In cases where unmanned vehicles having artificialintelligence are employed, for example, if only obstacle 74 data aresupplied to the vehicle at issue, the unmanned vehicles will be able tofollow a logic engine, negotiate a route that avoids the obstacle 74,and arrive at a target dumping point 72.

An embodiment aspect will now be described wherewith it is easy togenerate guided travel courses when the course area or target pointchanges.

In FIG. 15, course area 1 is a work area (loading area or dumping area)at a mining facility. An unmanned off-road dump truck 2 that is anunmanned moving body arrives at position S_(P) at an entrance branchpoint in this course area 1, then travels toward position T_(P) that isa movement target point over a guidance course that will be describedbelow, and performs prescribed work (loading or dumping work) at thatposition T_(P).

The unmanned off-road dump truck 2 (hereinafter called an unmanned dumptruck) is equipped with a travel control system such as is diagrammed inFIG. 13.

In FIG. 13, a mode setting unit 3 is for setting a measurement mode andan automatic operation mode, configured by a switch or switches, forexample.

A position measurement unit 4 is for detecting the current travelposition of the unmanned dump truck 2 using a GPS (global positioningsystem), tire revolution counting sensor for obtaining distance traveledinformation, and/or an optical fiber gyro for obtaining travel directioninformation, or the like (not shown).

FIG. 14 provides an example of a guidance course generation procedure.

In this procedure, first, a routine for inputting the shape of thecourse area 1 is executed (step 100).

When inputting the shape of the course area 1, an area measuring dumptruck (hereinafter called measuring dump truck)(not shown) is driven.That is, an operator boards this measurement dump truck, operates themode setting unit 3 noted above to set the measurement mode noted above,and then drives the dump truck 2 along the boundary of the course area1.

At such time, the position measurement unit 4 in the measurement dumptruck detects the travel position of that measurement dump truck momentby moment, and records it in a course area memory unit 6. Accordingly,the shape of the course area 1 will be stored in the course area memoryunit 6 as a sequence of travel position coordinate points.

In cases where there is area which cannot be traveled inside the coursearea (such as areas where there are large rocks), the measurement dumptruck is moved to the vicinity thereof, and a relative range from thatposition is either entered manually or entered by an operator on ascreen using a graphic interface.

The communications unit 7 indicated in FIG. 13 is for conductingcommunications with a monitoring station 8 located at a prescribedlocation. The communications unit 7 in the measurement dump truckdescribed above transmits data to the monitoring station 8 indicatingthe shape of the measured course area.

Now, the loading operation of the working unmanned dump truck 2 is doneby bringing the dump truck 2 alongside a loading apparatus such as awheel loader or power shovel that is digging ore, and having thatloading apparatus load the ore into the dump truck.

The position T_(P) at the movement target point noted earlier is theloading position for the loading apparatus, but this loading positionwill change as the work progresses.

That being so, this embodiment makes provision for obtaining theposition of the bucket of the power shovel or wheel loader and the angleof incursion of the unmanned dump truck 2 using a GPS on the loadingapparatus and a geomagnetic azimuth sensor.

The loading apparatus is equipped with a radio communication device, andtransmits the bucket position as the position T_(P) at the movementtarget point during loading to the monitoring facility 8 noted earlier.

Furthermore, the movement target point position T_(P) can be obtained,even when provision is made for indicating the relative position fromthe previous loading position, following changes in the position of theloading apparatus, as noted in Japanese Patent Application Laid-Open No.9-44242.

The monitoring station 8 transmits data indicating the shape of thecourse area, the position S_(P) of the entrance branch point (movementorigin) of the course area 1, and the movement target point positionT_(P) to the working unmanned dump truck 2.

Thereupon, a processor 5 in the unmanned dump truck 2 inputs the branchpoint position S_(P) and the movement target point position T_(P) viathe communications unit 7 (step 101), and then initializes at zero aguidance course generation number n and best evaluation value E best,described below, respectively (step 102).

Then, the processor 5 randomly sets the coordinates of a position M_(P)at one intermediate point in the course area 1 and the azimuth angle ofthe unmanned dump truck 2 at that intermediate point position M_(P)(step 103), and generates a guidance course for the unmanned dump truck2 that connects the branch point position S_(P) and the intermediatepoint position M_(P) (step 104). Now, if the direction vector of theunmanned dump truck 2 at the branch point position S_(P) is made spv,the same direction vector at the intermediate point position M_(P) madempv, and the same direction vector at the target point position T_(P)made tpv, as diagrammed in FIG. 15, the procedure for generating theguidance course in step 104 will be as follows.

(A) Case where the position M_(P) exists on the straight line S_(P)+mspv, as diagrammed in FIG. 16 and FIG. 17:

(a-1)

When spv=mpv, the straight line connecting the positions S_(P) and M_(P)is generated as the guidance course, as diagrammed in FIG. 16.

(a-2)

When spv≠mpv, circles S1 and S2 satisfying conditions 1 and 2 notedbelow are established, and a line made up of combinations of arcs onthose circles S1 and S2 intervening between the positions S_(P) andM_(P) is generated as the guidance course.

Condition 1: The circumference of the circle S1 passes through the pointS_(P) and the straight line S_(P)+k spv is tangent to that circle S1.The circumference of the circle S2 passes through the position M_(P) andthe straight line M_(P)+1 mpv is tangent to that circle S2.

Condition 2: The center of the circle S1 is on the side toward theposition M_(P) as seen from the position S_(P), and the center of thecircle S2 is on the side toward the position S_(P) as seen from theposition M_(P).

Condition 3: The circles S1 and S2 are of equal diameter and mutuallytangent.

(B) When the position M_(P) does not exist on the straight line S_(P)+mspv, and both spv≠mpv and spv≠−mpv are true, the intersection SM_(P)between the straight line S_(P)+m spv and the straight line M_(P)+n mpvis found, as diagrammed in FIGS. 18 to 22.

(b-1)

When in front of the position S_(P) and behind the position M_(P), astraight line that passes through the position S_(P) and contains thevector spv, and a circle S3 to which a straight line that passes throughthe position M_(P) and contains the vector mpv is tangent isestablished, and a guidance course is generated that passes over acircular arc on the circle S3 existing between the positions S_(P) andM_(P) and the straight line, as diagrammed in FIG. 18.

In other words, when the distance between the intersection SM_(P) andthe position S_(P) is shorter than the distance between the intersectionSM_(P) and the position M_(P), a circular arc that extends from theposition S_(P) through the circle M_(P) to the intersection with astraight line parallel to the vector mpv, and a line segment thatextends from that intersection to the position M_(P) are generated asthe course.

Conversely, when the distance between the intersection SM_(P) and theposition M_(P) is shorter, a course is generated which comprises a linesegment extending from the position S_(P) to the point where thestraight line containing the vector spv touches the circle, and the arcon the circle extending from that tangent point to the position M_(P).

(b-2)

When the intersection SM_(P) is behind the position S_(P) and theposition M_(P), as diagrammed in FIG. 19, or when the intersectionSM_(P) is in front of the position S_(P) and the position M_(P), asdiagrammed in FIG. 20, circles S4 and S5 that satisfy conditions 1 to 3noted below, respectively, are established, and a line comprisingcombinations of arcs on those circles S4 and S5 existing between thepositions S_(P) and M_(P) is generated as the guidance course.

Condition 1: The circle S4 passes through the position S_(P) and astraight line containing the vector spv is tangent thereto. The circleS5 passes through the position M_(P) and a straight line containing thevector mpv is tangent thereto.

Condition 2: The center of the circle S4 is on the position M_(P) sideas seen from the position S_(P), and the center of the circle S5 is onthe position S_(P) side as seen from the position M_(P).

Condition 3: The circles S4 and S5 have the same diameter and aremutually tangent.

(b-3) When the intersection SM_(P) is behind the position S_(P) and infront of the position M_(P), as diagrammed in FIG. 21, a straight linecontaining the vector spv and a circle S6 to which a straight linecontaining the vector mpv is tangent are established. Then a linecomprising a straight line extending from the position S_(P) to thepoint where the straight line containing the vector spv touches thecircle S6, and the arc on the circle S6 extending from that tangentpoint to the position M_(P), is generated as the guidance course.

(C) When the position M_(P) does not exist on the straight line S_(P)+mspv, the vectors spv and mpv are mutually parallel, and spv=mpv, asdiagrammed in FIG. 22, circles S4 and S5 satisfying the conditions notedunder (b-2) are established, and a line comprising combinations of arcson those circles S4 and S5 existing between the positions S_(P) andM_(P) is generated as the guidance course.

(D) When the position M_(P) does not exist on the straight line S_(P)+mspv, the vectors spv and mpv are mutually parallel, and spv=−mpv, asdiagrammed in FIG. 23 and FIG. 24:

(d-1)

When the inner product (spv, M_(P)−S_(P)) of the vector spv and a vectordirected from the position S_(P) to the position M_(P) is such that(spv, M_(P)−S_(P))>0, as diagrammed in FIG. 23, a circle S7 thecircumference whereof passes through the position M_(P) and to which thestraight line S_(P)+k spv and the straight line M_(P)+1 mpv are tangentis established. Then a line comprising a straight line extending fromthe position S_(P) to the point where the tangent S_(P)+k spv touches acircle 8, and an arc on the circle 8 extending from that tangent pointto the position M_(P), is generated as the guidance course.

(d-2)

When the inner product (spv, M_(P)−S_(P)) is such that (spv,M_(P)−S_(P))<0, a circle S9 that passes through the position S_(P) andto which the straight line S_(P)+k spv and the straight line M_(P)+1 mpvare tangent is established. Then a line comprising an arc on the circleS9 extending from the position S_(P) to the point where the straightline M_(P)+1 mpv touches a circle S10, and a straight line extendingfrom that tangent point to the position M_(P), is generated as theguidance course.

The procedures for generating guidance courses for the unmanned dumptruck 2 between the entrance branch point position S_(P) and theintermediate point position M_(P) described earlier are as describedabove. In the procedures for generating courses diagrammed in FIGS. 19,20, and 22, the diameters of two circles are set equal, but this is doneto simplify the computations, and it is possible to generate courseswithout setting the diameters of the circles equal.

Next, the processor 5 generates a guidance course between theintermediate point position M_(P) and the target point position T_(P)(step 105). The generation of this guidance course, however, follows theprocedures for generating the guidance course between the branch pointposition S_(P) and the intermediate point position M_(P) described inthe foregoing, and so is not further described here.

In step 103 described above, furthermore, coordinates for the positionM_(P) at the intermediate point are set randomly, but it is alsopermissible to provide so that coordinates are set sequentially from thecoordinates of a prescribed end or edge of the course area 1. In step105, moreover, when the guidance course is generated between theintermediate point position M_(P) and the target point position T_(P),it is permissible to establish one or a plurality of other intermediatepoints between those positions as may be necessary.

Thus is completed the generation of one guidance course extending fromthe entrance branch point position S_(P) through the intermediate pointposition M_(P) to the target point position T_(P), such as the guidancecourse exemplified in FIG. 25, for example. Thereupon the processor 5computes the minimum distance between that guidance course and theboundary of the course area described earlier (step 106).

That is, the guidance course generated as described in the foregoing isrepresented as a sequence of coordinate points in like manner as theshape of the course area 1. Thereupon, the processor 5 finds thedistances between the line segments indicated by points on the guidancecourse and the line segments indicated by points on the course area 1,and determines that minimum distance.

Now, it is preferable that the guidance course generated be establishedso that the distance from the boundary of the course area 1 becomes asgreat as possible, so that the unmanned dump trucks 2 can move with thelargest turning radius, and so that the dump trucks 2 can reach theposition T_(P) at the target pot in the shortest possible distance.

Thereupon, the processor evaluates the guidance course generated asdescribed in the foregoing, using the evaluation functions noted below(step 107).

E=f 1{min(distance from edge)}+f 2 (minimum R)+f 3(length of course)

where min(distance from edge) is the minimum distance between theguidance course and the boundary of the course area 1; minimum R is theminimum value of the radiuses of the circular arc portions of theguidance course; and length of course is the length of the guidancecourse.

In step 108, a determination is made as to whether or not the minimumdistance noted above is smaller than ½ the vehicle width, and in step109, a determination is made as to whether or not it is smaller than theminimum radius noted above (the minimum turning radius of the dump truck2).

If the minimum distance is smaller than ½ the vehicle width, thatsuggests the possibility of the dump truck 2 conflicting with theboundary of the course area 1, and if the minimum radius is smaller thanthe standard radius, that suggests that the guidance course generatedcontains portions where the dump truck 2 cannot turn around.

When the results of the determinations made in steps 108 and 109 hereare both YES, a routine is executed to make the evaluation value E avalue of 0 (step 110).

In step 111, a determination is made as to whether or not the evaluationvalue E is larger than the best evaluation value E best obtained thusfar.

When the result of the determination made in step 111 is YES, the bestevaluation value up till then is updated by the evaluation value E, andthe intermediate point position M_(P) established in step 103 and theguidance course generated in steps 104 and 105 are stored in theguidance course memory unit 9 indicated in FIG. 13 (step 112).

Next, in step 113, a determination is made as to whether or not theevaluation value E is larger than the preset standard evaluation value.If the evaluation value E is larger than the standard evaluation value,the intermediate point position M_(P) and guidance course currentlystored in the guidance course memory unit 9 are established as theadopted intermediate point position and the adopted guidance course(step 114).

If the results of the determinations made in steps 111 and 113 are NO,on the other hand, the guidance course generation number n (set suitablyaccording to the size of the course area, etc.) is incremented by 1(step 115), and a determination is made as to whether or not thegeneration number n has reached a set iteration (step 116).

If the generation iteration n has not reached the set iteration, theprocedure returns to step 103, whereas, if that iteration n has reachedthe set iteration, the procedure moves to step 114.

As already noted, when the results of the determinations made in steps108 and 109 are YES, a routine is executed to make the evaluation valueE a value of 0. Therefore, the result of the determination made in step111 becomes NO, and, as a consequence, the procedure returns to step 103and generation processing for another course is executed.

What that means is that, based on the procedure described above, whenthe guidance course generated contains a portion wherein the dump truck2 cannot turn around, or there is a possibility of the dump truck 2conflicting with the boundary of the course area, another guidancecourse, different from that guidance course, will be generated.

Ultimately, then, a guidance course is generated that contains nosegment wherein the dump truck 2 cannot turn around and wherewith thereis no danger of a conflict occurring.

The minimum distance that is the subject of the determination in step108 contains course area measurement errors. Also, when the dump truck 2is guided based on the course data described earlier, errors such asposition measurement errors and travel control errors and the likeoccur. Accordingly, in order to raise the reliability of the conflictcheck made in step 108, decision criteria that are adjusted for sucherrors should be employed in ½ the vehicle width noted earlier.

As is evident from the foregoing description, based on the proceduresdescribed above, a guidance course is generated, on the basis of thecoordinates of a randomly designated intermediate point position M_(P),that extends from an entrance branch point position S_(P), passesthrough the intermediate point position M_(P), and arrives at the targetpoint position T_(P), that is, more specifically, a guidance courseconfigured by straight lines, circular arcs, or a combination thereof

When the evaluation value for the guidance course generated is higherthan the standard evaluation value, or when the guidance coursegeneration iteration n has reached a set iteration, the adoptedintermediate point position and the adopted guidance course aredetermined.

The processor 5 transmits that adopted intermediate point position andthat adopted guidance course by the communications unit 7 indicated inFIG. 13 to the monitoring station 8.

In the guidance course generation method described in the foregoing, theintermediate point position M_(P) is randomly established, but thatintermediate point position M_(P) may instead be establishedsequentially from any edge position in the course area 1. Alternatively,a prescribed zone may be designated in the course area and theintermediate point position M_(P) sequentially established from any edgeposition in that zone.

In the guidance course generation method described in the foregoing,furthermore, the guidance course is configured by straight lines,circular arcs, or a combination thereof, but it is also possible toconfigure a guidance course wherein the intervals between the positionsS_(P) and M_(P) and between the positions M_(P) and T_(P), respectively,are connected by a spline curve, or, alternatively, the configurationmay be made by combining straight lines, circular arcs, and splinecurves.

In the description above, moreover, guidance courses are automaticallygenerated wherein no conflicts arise, but provision may also be made sothat every time one course is generated the response of an operator isrequested for that course.

In other words, an embodiment aspect can be adopted wherein, every timeone course is generated, indications are made as to whether conflictsarise or the possibility of conflicts exists with that course, and anoperator then selects the best course based on those indications.

Next, the guided travel of a dump truck 2 using the guidance coursesdescribed above is described.

An unmanned dump truck 2 that has been automatically driven to theentrance branch point position S_(P) described earlier is temporarilystopped by a stop command from the monitoring station 8. Then, at thepoint in time where an automatic operation command is received from themonitoring station 8, automatic operation travel is commenced inside thecourse area 1.

More specifically, the processor 5, based on the automatic operationcommand, starts a travel mechanism unit 10, causing the unmanned dumptruck 2 to travel, or, simultaneously, verifies the current position ofthe unmanned dump truck 2 based on the output of the travel positionmeasurement unit 4, and, based on that current position and the guidancecourse stored in the guidance course memory unit 9, controls a steeringmechanism unit 11 in the dump truck 2 so that that unmanned dump truck 2is positioned on that guidance course. Hence the unmanned dump truck 2will travel over the guidance course and arrive at the target pointposition T_(P).

In the embodiment aspect(s) described in the foregoing, the unmanneddump truck 2 branch point S_(P) is established as the entrance to thecourse area 1. However, in cases where the boundary between the entranceto that course area and the so-called whole road that is the travelroute for the dump truck 2 up to the entrance to the course area 1 isnot clear, or the course area 1 is very long, the branch point S_(P) maybe made at any position on that whole road.

In that case, that branch point S_(P) may be determined on a one-to-onebasis as a position on the whole road removed a prescribed distance fromthe target point position T_(P), or, alternatively, the branch pointposition S_(P) may be expressed using a parameter for determining aposition on the whole road (such, for example, as the distance ofmovement of the dump truck 2 from a prescribed departure point on theguidance course established beforehand on the whole road), searching forthat parameter together with the intermediate point position M_(P), andthen determining the branch point S_(P).

In the embodiment aspects described in the foregoing, furthermore, theintermediate point position M_(P) is given in terms of rectangularcoordinates (X, Y), but that intermediate point position M_(P) can alsobe given in terms of cylindrical coordinates (θ, 1). It is alsopermissible to use two perpendicular vectors as the standard in thecoordinate system, or to use any vectors having different directions,such, for example, as the entrance branch point position S_(P) or targetpoint position T_(P) described earlier.

The intermediate point position M_(P) can also be given as follows.

That is, a circle can be drawn which passes through the entrance branchpoint position S_(P) and touches the direction vector spv, and theintermediate point position M_(P) then established by the radius of thatcircle and the length of the arc from the position S_(P) in that circle.

Similarly, moreover, a circle can be drawn which passes through themovement target point position T_(P) and touches the direction vectortpv, and the intermediate point position M_(P) then established by theradius of that circle and the length of the arc from the position T_(P)in that circle.

In cases like that, either a partial guidance course extending from theposition S_(P) to the position T_(P), or a partial guidance courseextending from the position T_(P) to the intermediate point positionM_(P), will be produced simultaneously with the establishment of thatintermediate point position M_(P), so it is then no longer necessary toproduce this partial guidance course according to the algorithmdescribed earlier.

The partial guidance courses described above will be configured ascourses wherein the dump truck 2 is fully able to make turns, by theradius of the circle being set equal to or greater than the minimumturning radius of the dump truck 2.

In the foregoing description, the intermediate point position M_(P) isestablished drawing one circle, but a plurality of circles can be drawn,and that intermediate point position M_(P) established by the radiusesof those circles and the arc lengths on those circles.

More specifically, as diagrammed in FIG. 26, for example, a circle S10that passed through the movement target point position T_(P) and istangent to the vector tpv and another circles S11 of the same radiustangent to that circle S10 can be drawn, and an intermediate pointposition M_(P) referenced to the movement target position T_(P) thenestablished on the basis of the radiuses of those circles, the length ofthe arc extending from the position T_(P) to the point where the circlesS10 and S11 are tangent, and the length of the arc extending from thattangent point to the intermediate point position M_(P).

There are two different circles that pass through the movement targetpoint position T_(P) and touch the vector tpv, namely the circle S10(drawn in the diagram) positioned above the vector spv, and a circle(not shown) positioned below the vector spv.

That being so, in order to draw the two circles noted above andestablish the intermediate point position M_(P), a total of fourparameter values will be designated, namely the radius of the circles,the length of the arc in one circle, the length of the arc in the othercircle, and a flag indicating whether the circle on the left ispositioned below or above the tangent line. It is not absolutelynecessary, either, to set the radiuses of the two circles equal.

When the intermediate point position M_(P) is established drawing aplurality of circles, as described in the foregoing, a partial guidancecourse reaching to that intermediate point position M_(P) will beproduced simultaneously with that establishment, so it will no longer benecessary to produce that partial guidance course using the algorithmdescribed earlier.

That partial guidance course also will contain no portion wherein theunmanned dump truck 2 cannot turn around, by the setting of the radiusesof the circles equal to or greater than the minimum turning radius ofthe dump truck 2.

Now, the position measurement unit 4 indicated in FIG. 14 comprises theGPS described earlier, but, when the antenna 12 for that GPS is deployedat the front center of the unmanned dump truck 2, as diagrammed in FIG.27, the GPS will measure the position where that antenna 12 is deployedas the travel position of the unmanned dump truck 2.

Accordingly, when the unmanned dump truck 2 is made to travel along theboundary of the course area 1, and an attempt is made to measure theshape of the course area 1 based on the results of the positionsdetected moment by moment by the GPS obtained at such time, the measuredshape of the course area 1 will become a shape wherein the boundary ofthe actual course area 1 is shifted toward the inside by a distance thatis approximately half the vehicle width of the unmanned dump truck 2. Inother words, the shape of the course area 1 so measured will contain anerror corresponding to a distance that is approximately half the vehiclewidth.

In FIG. 28 is exemplified a procedure that reduces the error describedabove to the extent possible. That procedure is executed in theprocessor 5, but, when it is being executed, the measurement mode is setby the mode setting unit 3 described earlier.

The GPS outputs data (hereinafter called GPS data) indicating theposition of the dump truck 2 at prescribed periods. With the procedurediagrammed in FIG. 28, after a flag and the dump truck 2 azimuth anglehave respectively been initialized at 0 (step 200), read-in GPS data{GPS x, GPS y} are set as the GPS data {GPS old x, GPS old y} that wereoutput the previous period (step 201).

Next, when the GPS data {GPS x, GPS y} are being read in (step 202), adetermination is made as to whether or not the flag has been set to 1(step 203).

At the current point in time, the flag is 0, wherefore the result of thedetermination made in step 203 will be NO. That being so, after thatflag has been set to 1 (step 204), the procedure returns to step 201.

Subsequently, the routines in steps 201 to 203 will be executed again,but the result of the determination made in step 203 will be YES due tothe fact that the flag is set to 1.

Thus the GPS data {GPS old x, GPS old y} output the previous period andthe GPS data {GPS x, GPS y)} output in the current period are obtained,wherefore the azimuth angle of the unmanned dump truck 2 is computedaccording to the formula 1 below (step 205).

Angle=a tan2(GPS y−GPS old y, GPS x−GPS old x)  (1)

where a tan2 is an arctangent function for finding angles adjusted forthe X and Y signs.

Next, a determination is made as to whether or not the left edge of theunmanned dump truck 2 is to be made the measurement position (step 206).The measurement position indication switch 13 indicated in FIG. 14selectively designates the left edge or right edge of the unmanned dumptruck 2 as the measurement position, and the determination made in step206 is made based on the indication of that switch 13.

When the left edge measurement position has been designated, theposition of that left edge is computed as the travel position, based onformulas (2) and (3) below (step 207). When the right edge measurementposition has been designated, on the other hand, the position of thatright edge is computed as the travel position, based on formulas (4) and(5) below (step 208).

Edge x=GPS x+11*cos(Angle)−12*sin(Angle)  (2)

 Edge y=GPS y+11*cos(Angle)−12*cos(Angle)  (3)

Edge x=GPS x+11*cos(Angle)−13*sin(Angle)  (4)

Edge y=GPS y+11*cos(Angle)−13*cos(Angle)  (5)

where 11, 12, and 13 are parameters indicating the positionalrelationship of the GPS antenna 12 on the dump truck 2 (cf FIG. 27).

The computed travel position (Edge x, Edge y) is stored in the coursearea memory unit 6 (step 209), and then the procedure noted above isrepeated.

Accordingly, if, with the left edge measurement position noted earlierdesignated, the unmanned dump truck 2 is made to travel so that the leftedge thereof follows the boundary of the course area 1, the shape of thecourse area 1 can be measured with extremely good precision.

In the procedures described in the foregoing, furthermore, the azimuthangle of the unmanned dump truck 2 is calculated on the basis ofquantitative positional changes in the unmanned dump truck 2, but thatazimuth angle may also be measured using an optical fiber gyro orgeomagnetic sensor. A so-called sensor fusion technique for improvingdetection precision using a plurality of different sensors complexly canalso be employed in the measurement of the azimuth angle.

It is also possible, incidentally, to improve the precision of measuringthe shape of the course area 1 by altering the position in which the GPSantenna 12 is actually deployed.

In that case, connectors for attaching the GPS antenna 12 are deployedat the left edge and the right edge of the unmanned dump truck 2, andthe GPS antenna 12 selectively coupled to one of those connectorsaccording to how the dump truck 2 is operated relative to the coursearea.

It is of course also possible to make the configuration such thatseparate GPS antennas are attached to the left edge and right edge,respectively, and have those antennas selectively connected to the GPSreceiver by switching means.

If the course area is the loading area described earlier, that coursearea 1 will expand as the digging work of the excavating machineproceeds. That is, the shape of the course area 1 will change.

When the shape of the course area 1 changes, errors will appear in theminimum distance calculated in step 106 diagrammed in FIG. 14, and thatwill have an effect on the evaluation value in step 107. As the coursearea 1 changes and becomes larger, moreover, it will also becomenecessary to modify the guidance course of the unmanned dump truck 2.

In order to cope with shape changes in the course area 1, the operationof measuring the shape of the course area 1 may be implementedperiodically, but that will reduce work performance, and so is not thebest approach.

Accordingly, a procedure is described below for updating the shape ofthe course area 1 without implementing the measurement operationdescribed earlier.

A loading machine (loading apparatus) 14 such as a wheel loader ispositioned at the loading place in the course area 1, as diagrammed inFIG. 29.

This loading machine 14 is equipped with a position measuring unit 15comprising a GPS, an azimuth measuring unit 16 comprising an opticalfiber gyro or the like, a communications unit 17 for communicating withthe monitoring station 8, a guidance course memory unit 18, and aprocessor 19, as diagrammed in FIG. 32.

Data indicating the shape of the course area 1 transmitted from themonitoring station 8, after being received by the communications unit17, are stored in the processor 19 via the processor 18. The dataindicating the shape of the course area 1 relate to the course areaactually measured by the unmanned dump truck 2. That course area ishereinafter called the initial course area.

As diagrammed in FIG. 33, the processor 19 inputs the current positionof the loading machine 14 measured by the position measuring unit 15(step 300), calculates the distance between that position and theinitial course area 1 (step 301), and makes a determination as towhether or not that distance has become 0 (step 302).

The loading machine 14, as indicated by the arrow in FIG. 29, advancestoward the outside of the initial course area 1 as the ore excavationprogresses. As a consequence, the distance between that position and theboundary of the initial course area 1 gradually diminishes.

Then, when the loading machine 14 advances to the point where thedistance noted above becomes 0, as diagrammed in FIG. 30, the result ofthe determination made in step 302 will become YES, so a course areashape updating routine is executed in the guidance course memory unit 18(step 303).

That is, the course area shape data stored in the guidance course memoryunit 18 are updated so that the area of advance of the loading machine14 is added to the initial course area.

As a result of that updating process, data indicating an enlarged coursearea shape, as diagrammed in FIG. 31, will be stored in the guidancecourse memory unit 18. That updated course area will subsequently bere-updated when the loading machine 14 has advanced further.

The area occupied by the loading machine 14 and the positions of theleft and right front edges are computed by the processor 19, based onthe position, shape, and azimuth of the loading machine 14.

The updated course area shape is transmitted via the communications unit17 to the monitoring station 8. There the monitoring station 8 updatesthe movement target point position T_(P) described earlier in responseto the movement of the loading machine 14, and transmits that updatedmovement target point position T_(P) and data indicating the updatedcourse area shape to the dump truck 2.

The processor 5 of the dump truck 2 indicated in FIG. 13 executes theguidance course generation procedure diagrammed in FIG. 15, based on themovement target point position T_(P) and the course area shape after theupdating described above. As a result, the dump truck 2 will be guidedalong the guidance course that has been adapted to changes in the coursearea shape until it arrives at the movement target point position T_(P).

In the foregoing description, the course area shape is updated on thebasis of changes in the position of the loading machine 14, but it isalso possible to update the course area shape on the basis of the formof work being done by the excavating machine, such as the form of thework being done by the power shovel 20 diagrammed in FIG. 34, forexample.

In that case, the power shovel 20 is provided with a three-dimensionalposition measurement unit 21 comprising a GPS or the like, a bucketposition measurement unit 22, a communications unit 23 for communicatingwith the monitoring station 8, a course area memory unit 24 for storingthe course area shape, and a processor 25, as diagrammed in FIG. 35.

The bucket position measurement unit 22 measures the three-dimensionalposition of the bucket 27 on the basis of the three-dimensional positionof the power shovel 20 measured by the three-dimensional positionmeasurement unit 21, the turning angles of the boom 25, arm 26, andbucket 27, and the turning angle of the upper turning body 28.

Data indicating the shape of the course area (i.e. the initial coursearea) 1 transmitted from the monitoring station 8 are stored via thecommunications unit 23 and the processor 25 in the course area memoryunit 24.

In FIG. 36 is exemplified a course area shape updating procedureexecuted in the processor 25.

With this procedure, the position of the power shovel 20 measured by thethree-dimensional position measurement unit 21 is input (step 400), andthen the position of the bucket 27 measured by the bucket positionmeasurement unit 22 is input (step 401).

The height of the site of excavation by the power shovel 20 above theground becomes lower as the excavation progresses until it eventuallycoincides with the ground height inside the course area. Thereupon, inthe next step, step 402, a determination is made as to whether or notthe height of the bucket 27 coincides with the initial ground heightinside the course area.

When making the decision in step 402, the height of the bucket 27 can beobtained from the output of the bucket position measurement unit 22. Theinitial ground height inside the course area is measured beforehand byappropriate means.

If the bucket 27 strikes the ground inside the course area, the heightposition at the three-dimensional position output by the bucket positionmeasurement unit 22 will indicate that ground height, wherefore it isalso possible for the power shovel 20 to measure the initial groundheight itself.

When the result of the determination made in step 402 becomes YES, thecourse area updating process is executed (step 403). That is, the coursearea shape data stored in the course area memory unit 24 are updated sothat the area commanded by the bucket 27 is added to the initial coursearea. Those updated shape data are re-updated subsequently as theexcavation being done by the power shovel 20 advances further.

It is possible to update the shape of a course area 1 even when thatcourse area is the dumping area described earlier.

That is, with a dumping area, the shape of that area will change inconjunction with the dumping operations of the dump truck 2, but theposition of that dumping will be known from the position of the dumptruck 2, and the dumping range will be known from the quantity ofdumping done by that dump truck.

That being so, the course area shape data are updated so that theportion of the course area corresponding to that dumping position issubtracted from the dumping range. The updated shape data are of coursere-updated in conjunction with subsequent dumping operations.

Now, in the embodiment aspect described in the foregoing, a measuringdump truck is actually made to travel about in order to measure theshape of a course area 1, but it is also possible to deploy a laserprojector that projects a laser beam in horizontal directions whileturning about a vertical shaft in, for example, the entrance portion ofthe course area 1, and a light receiver for receiving reflected lightfrom that laser beam (light reflected from the boundary of the coursearea 1), and measuring the shape of that course area 1 on the basis ofthe time from the projection of that laser beam until the reception ofthe reflected light.

Based on that method, it is possible to measure the entire course area,but it is also permissible to measure only the shapes of zones in thatarea where the shape has been altered, using a low-power laser beam.

It is further possible to measure the shapes of such zones of alteredshape by causing the measuring dump truck described earlier to travel inthose zones of altered shape.

With the embodiment described in the foregoing, the height of the bucket27 of the power shovel 20 is measured by the bucket position measurementunit 22 and, when that height measured by the bucket positionmeasurement unit 22 has become the initial ground height in the coursearea 1, the course area 1 is expanded and updated just by the part ofthe area occupied by the bucket 27.

In many cases, however, the loading machine 14 is not provided with aworking member position measuring unit such as the bucket positionmeasurement unit 22. That being so, an embodiment is described nextwherewith it is possible to update the course area 1 even when noworking member position measuring unit such as the bucket positionmeasurement unit 22 is carried on board.

Embodiment 1

It is assumed that the position of a loading machine 14 such as anexcavator or wheel loader is measured by a position measuring apparatussuch as a GPS. The position measured by the loading machine 14 is set tothe movement target point T_(P) of the unmanned dump truck 2. If theloading machine 14 is an excavator, for example, the position thereof ismeasured by one or more GPS units attached to the main body of theexcavator, or to an arm or boom thereof

FIG. 39 is a diagram for describing an updating process for expanding acourse area 1 based on the current position of a loading machine 14measured by that same loading machine 14. In FIG. 39, the boundary lineof the course area 1 is indicated by the broken line designated 1 a.

As diagrammed in FIG. 39(a), the loading machine 14 performs anexcavation operation by so-called top loading, as diagrammed in FIG. 34.Accordingly, as the excavation and loading operations of the loadingmachine 14 progress, the situation diagrammed in FIG. 39(a) changes tothe situation diagrammed in FIG. 39(b). In this manner, the operator ofthe loading machine 14 levels off the work surface according to theexcavation, and expands the course area 1 again to make it possible forthe unmanned dump truck 2 to travel.

When in this case a working member position measuring unit such as thebucket position measurement unit 22 is carried on board the loadingmachine 14, as in the embodiment described earlier, positional data canbe acquired for the portion of the course area 1 to be expanded from theposition of the bucket 27 when the height of the bucket measured by thebucket position measurement unit 22 has become the initial ground heightin the course area 1. The course area 1 is then expanded just by theportion of the area occupied by the bucket 27.

In cases where no working member position measuring unit such as thebucket position measurement unit 22 is carried on board the loadingmachine 14, the position where the course area 1 expands and the rangeof that expansion are found on the basis of the current position of theloading machine 14 measured by the position measuring unit (GPS) carriedon board the loading machine 14, that is, on the basis of the movementtarget point T_(P) (i.e. the loading position) of the unmanned dumptruck 2. More specifically, the area designated as the target positionT_(P) of the unmanned dump truck 2 is an area where ground surfaceroughness and the like have been smoothed out by the loading machine 14.This smoothed area is an area that is guaranteed by the operator of theloading machine 14 to be suitable for the unmanned dump truck 2 totravel over.

Thereupon, every time the current position of the loading machine 14 ismeasured by the position measuring apparatus (GPS) carried on board theloading machine 14 and the movement target point T_(P) (loadingposition) of the unmanned dump truck 2 is given, that movement targetpoint T_(P) is deemed the position where the course area 1 is to beexpanded, the course area 1 is successively expanded, and the coursearea 1 is subjected to automatic updating processing.

How to set the range wherein the course area 1 will be expanded when themovement target point T_(P) is given is discretionary. The range whereinthe course area 1 is expanded can be set, for example, to the size ofthe vehicle occupation range 2 a centered on (referenced to) themovement target point T_(P) (loading position) of the unmanned dumptruck 2, as diagrammed in FIG. 39(a). When setting the range 2 aoccupied by the vehicle 2, a certain degree of latitude may beanticipated. Thus, as diagrammed in FIG. 39(a), the course area 1 willbe successively expanded, by the amount of the range 2 a occupied by thevehicle 2, every time the movement target point T_(P) of the unmanneddump truck 2 is given.

When the movement target point T_(P) for the unmanned dump truck 2 isgiven, the unmanned dump truck 2 moves toward that movement target pointT_(P). The travel course required for this unmanned dump truck 2 to movetoward the movement target point T_(P) may also be deemed to be thatwhich has been smoothed by the loading machine 14, and it is possiblesimultaneously to add that to the expansion range of the course area 1.

Embodiment 2

An embodiment is described next wherewith the course area 1 is updatedso that it contracts. In this case, the loading machine 14 performsexcavation and loading operations in the situation d in FIG. 40(b).Thus, as the work being done by the loading machine 14 progresses, theboundary line 1 a of the course area 1 will move toward the inside, andthe course area 1 will contract.

A loading machine 14 such as an excavator moves a bucket to dig earth,then turns (rotates) its main body (upper turning body), and transportsthe ore in the bucket to the unmanned dump truck 2 and loads it, thusperforming a chain of excavation and loading operations. The turningspeed of the main body of the loading machine 14 is fast compared to thevehicle moving speed. For that reason, the operation of transporting theearth (ore) after digging the earth (i.e. the loading operation) isperformed by rotating the main body while the vehicle itself remainsstationary. Accordingly, when loading earth into the unmanned dump truck2, the earth within a certain range referenced to the turning centerposition of the main body of the loading machine 14 will be excavatedand that ground will be smoothed. Hence, at the point in time where thetarget point T_(P) for the unmanned dump truck is given, the areaexcavated (to be excavated) can be estimated with reference to theturning center position of the loading machine 14.

A loading machine 14 such as an excavator is capable of excavating anyarea within a range reachable by its arm, as diagrammed in FIG. 40(a).That being so, provision is made so that, at the point in time when thetarget point T_(P) (loading position) of the unmanned dump truck 2 isgiven, all of the area 14 b within the range reachable by the arm isexcluded from the course area 1, based on the position of the turningcenter of the loading machine 14 at that time. As a result, it ispossible to avoid the unmanned dump truck 2 intruding into an area beingexcavated, regardless of what work is being done by the loading machine14 within the area 14 b.

When the entire area 14 b reachable by the arm of the loading machine 14is excluded from the course area 1, however, the movement target pointT_(P) of the unmanned dump truck 2, if the condition is left unchanged,will end up being outside the course area 1. Thereupon, the process ofexcluding the range 14 b reachable by the arm of the loading machine 14is performed, making use of embodiment 1 also, so that the movementtarget point T_(P) for the unmanned dump truck 2 is set inside thecourse area 1.

That is, the target point T_(P) for the unmanned dump truck 2 is an areathat has been smoothed by the loading machine 14 and made negotiable byvehicles. Thereupon only the target point T_(P) is removed from insidethe circle 14 a reachable by the arm of the loading machine 14. That isbecause the possibility of areas within the range 14 a of the loadingmachine 14 being excavated is conceivable.

Embodiment 3

In embodiment 2, embodiment is also possible such that only a part ofthe range 14 b reachable by the arm of the loading machine 14, and notthe entirety thereof, is excluded from the course area 1. That is, inordinary mining operations, it is common not to begin excavating fromthe center of the course area where there is nothing, but to excavatewithin a certain range from the border 1 a of the course area 1, and toleave the remaining portions as course area capable of being traveledover by the unmanned dump truck 2. Also, as the excavation progresses,the loading machine 14 will repeatedly move at odd times in intervals of1 to 3 meters or so. Accordingly, even if the range excluded from thecourse area 1 is made about the size of the vehicle body, for example,the course area 1 that changes due to the excavation can be covered.Therefore, as the loading machine 14 moves, the areas 14 a (octagonalarea 14 a) that are each about the size of the vehicle body existingwithin a certain range from the boundary of the course area 1, insidethe circle 14 b of the range reachable by the arm of the loading machine14, are successively excluded from the course area 1, as diagrammed inFIG. 40(a).

When it has been determined that the loading machine 14 has moved at ahigh speed, the areas 14 c wherewith the distance from the boundary 1 aof the course area 1 becomes constant, in the circle 14 b of the rangereachable by the arm of the loading machine 14, are successivelyexcluded from the course area 1, as diagrammed in FIG. 41.

Embodiment 4

In cases where the excavation operation does not exhibit a certainregularity, the operator of the loading machine 14 may directlydesignate the range to be excluded from the course area 1. If theloading machine 14 is an excavator, for example, embodiment isconceivable such that, by having the operator press a button or the likewhen he or she has moved the bucket over the position that is to be dug,that current bucket position can be designated as the range to beexcluded from the course area 1. In such case, the direction and theposition of the turning center of the excavator are determined by aplurality of position measuring apparatuses (GPSs) deployed on theexcavator. Then the position of the bucket is calculated using thosevalues and the already known distance between the bucket and the centerof turning of the main body.

In embodiment 1 above was described an updating process for the casewhere the course area 1 expands, and in embodiments 2, 3, and 4 abovewere described updating processes for cases where the course area 1contracts. Provision may be made so that either updating processing forexpanding the course area 1 or updating processing for diminishing thecourse area 1 is performed according to the work situation. Embodimentis conceivable wherewith, for example, a selection switch is providedfor selecting whether to expand or diminish the course area 1 accordingto the form of the work being done by the loading machine 14, and eitheran updating process for expanding the course area 1 or an updatingprocess for diminishing the course area 1 is performed according to theresult of the selection made with that selection switch.

The guidance course described in the foregoing is obtained by aheuristic problem solving technique, and various methods have beenproposed for such solving techniques. With the simple Monte Carlomethod, multiple trials are conducted, and the trial yielding the bestevaluation function results is selected therefrom. With a method calledthe hill climbing method, trials are not conducted in all of the space,but a trial is conducted in a solution space near the previous trial,the evaluation value therefor is compared with the previous evaluationvalue, and the new trial is adopted when the evaluation value hasimproved. The hill climbing method is an effective technique forresolving heuristic problems at high speed.

With the hill climbing method, there are cases where the optimalsolution will not be selected when a local solution exists in thesolution space. When there is an island-shaped area into which entry isforbidden inside the course area, for example, a local solutionsometimes exists, in which case there is a possibility that the optimalsolution will not be selected.

Another heuristic method is the genetic algorithm (GA). This is acomputation method wherewith some data for a plurality of candidates areexchanged, “intersections” that make new candidates, and mutations thatalter some of the candidates are repeatedly implemented, and descendentsare created having better evaluation values.

This method performs mutations from the entire solution space, so thereis little likelihood that a local solution will be missed. Accordingly,the desired solution can be arrived at faster than with the Monte Carlomethod, for which reason this method is frequently employed.

In this embodiment the genetic algorithm is used, but the details willhave to be omitted here.

In this embodiment, guided travel course data are generated by providinga movement starting point S_(P) and a direction spv at that position, asdiagrammed in FIG. 15, but, instead of providing the movement startingpoint S_(P) and direction spv at that position, the guided travel coursemay also be generated by providing a plurality of point sequences on acourse that enters the course area 1. In that case, the following methodis conceivable as a method for selecting the plurality of pointsequences on the course that enters the course area 1. Specifically, itis only necessary to make trial changes, as with the intermediate pointM_(P), and select the case wherewith the evaluation function value isoptimized. Or the operator may make a discretionary selection. Or,instead of providing point sequences, the points may be on line segmentsor circular arcs or spline curves, and one location among thoseselected.

The evaluation functions for evaluating the guided travel courses in thepresent invention are not limited by those cited in the embodimentsdescribed in the foregoing. The subject of the evaluation may be thetime predicted for a guided travel course to be moved, for example. Inthat case, the shorter the movement time, the better the evaluationvalue. Or the position of a direction reversal may be made the subjectof evaluation. In that case, the closer the position of directionreversal, the better the evaluation value. Or the evaluation value maybe better the smaller the change in the attitude angle at the targetposition and the attitude angle at the position of direction reversal.

What is claimed is:
 1. A vehicle guidance system for guiding a pluralityof vehicles, comprising: memory means for storing positions of obstaclesat a work site common to the plurality of vehicles when the plurality ofvehicles travel simultaneously over that work site; updating means forupdating content stored in the memory means, the stored contentincluding common data for all of the vehicles; and guidance means forgenerating, based on the common data, travel course data for eachvehicle that does not conflict with the obstacles, and guiding theplurality of vehicles respectively along each of the generated travelcourses.
 2. The vehicle guidance system according to claim 1, in whichsome or all of the plurality of vehicles comprise obstacle detectionmeans for detecting obstacles; the vehicle guidance system furthercomprising: obstacle position measurement means for measuring positionsof those obstacles based on position of a vehicle when an obstacle hasbeen detected by the obstacle detection means; and wherein the memorymeans stores the positions of obstacles measured by the obstacleposition measurement means as positions of obstacles common to theplurality of vehicles; and the updating means updates the content storedin the memory means, based on the position of a new obstacle measured bythe obstacle position measurement means, every time a new obstacle isdetected by the obstacle detection means.
 3. The vehicle guidance systemaccording to claim 1, in which some or all of the plurality of vehiclescomprise: road surface condition detection means for detecting a roadsurface condition; and determination means for determining that acurrent road surface is an obstacle based on the road surface conditiondetected by the road surface condition detection means; wherein thememory means stores position of a vehicle at the time when the currentroad surface was determined to be an obstacle by the determination meansas position of an obstacle common to the plurality of vehicles; and theupdating means updates the content stored in the memory means every timethe determination means determines a new obstacle.
 4. The vehicleguidance system according to claim 1, in which some or all of theplurality of vehicles comprise: reception means for receiving signalsfrom other manned vehicles indicating that an obstacle exists invicinity of its own vehicle; transmission means for transmitting signalsindicating position of its own vehicle when a signal is receivedindicating that an obstacle exists in vicinity of its own vehicle; andobstacle position measurement means for receiving signals indicating avehicle position transmitted from the transmission means and formeasuring positions of obstacles near that vehicle based on the vehicleposition received; wherein the memory means stores the positions ofobstacles measured by the obstacle position measurement means aspositions of obstacles common to the plurality of vehicles; and theupdating means updates the content stored in the memory means, based onthe position of a new obstacle measured by the obstacle positionmeasurement means, every time a signal is received by the receptionmeans indicating that a new obstacle exists.
 5. The vehicle guidancesystem according to claim 1, wherein, when a manned or unmanned workvehicle having vehicle position measurement means for measuring positionof its own vehicle is present inside an area traveled over by theplurality of vehicles, the memory means stores the position of the workvehicle measured by the vehicle position measurement means as positionof an obstacle common to the plurality of vehicles, and the updatingmeans updates the content stored in the memory means every time theposition of the work vehicle is altered by the vehicle positionmeasurement means.
 6. The vehicle guidance system according to claim 5,wherein the updating means updates the content stored in the memorymeans every time the positions of the work vehicles are successivelychanged in conjunction with traveling of the work vehicles.
 7. Thevehicle guidance system according to claim 5, wherein the updating meansupdates the content stored in the memory means every time the workvehicle stops traveling and stopped position of that work vehicle ischanged.
 8. A vehicle guidance system wherein: each of a plurality ofvehicles is provided with vehicle position measurement means formeasuring current position of that vehicle; when position data fortarget points that should be reached by each of the plurality ofvehicles are given, data are generated for travel courses that passthrough those target points; and each of the plurality of vehicles ismade to guide that vehicle along its proper travel course whilecomparing the current vehicle position measured by the vehicle positionmeasurement means with positions on the generated travel course; thevehicle guidance system comprising: memory means for storing positionsof obstacles at a work site common to the plurality of vehicles when theplurality of vehicles travel simultaneously over that work site;updating means for updating content stored in the memory means; travelcourse generation means which, when position data on the target pointsare given, generate data for travel courses that pass through thosetarget points, based on content recorded in the memory means, so thatthere is no conflict with the obstacles; and guidance means for guidingthe plurality of vehicles, respectively, along travel courses generatedby the travel course generation means.
 9. A vehicle guidance systemwherein: each of a plurality of vehicles is provided with vehicleposition measurement means for measuring current position of thatvehicle; when position data for target points that should be reached byeach of the plurality of vehicles and position data for a course areacapable of being traveled by the plurality of vehicles are given, dataare generated for travel courses that travel inside that course area andpass through those target points; and each of the plurality of vehiclesis made to guide that subject vehicle along its proper travel coursewhile comparing the current vehicle position measured by the vehicleposition measurement means with positions on generated travel course;the vehicle guidance system comprising: memory means for storingpositions of obstacles at a work site common to the plurality ofvehicles when the plurality of vehicles travel simultaneously over thatwork site; updating means for updating content stored in the memorymeans; travel course generation means which, when position data on thetarget points and position data on the course area are given, generatesdata for the travel courses that travel inside the course area and passthrough the target points, based on content recorded in the memorymeans, so that there is no conflict with the obstacles; and guidancemeans for guiding the plurality of vehicles, respectively, along travelcourses generated by the travel course generation means.
 10. The vehicleguidance system according to claim 9, comprising: display means fordisplaying the course area on a display screen; and obstacle indicationmeans for indicating positions of obstacles on the display screen basedon relative positional relationship thereof with the course area on thedisplay screen; wherein the memory means stores the positions ofobstacles on the display screen indicated by the obstacle indicationmeans as positions of obstacles common to the plurality of vehicles; andthe updating means updates the content stored in the memory means everytime the position of an obstacle is newly indicated by the obstacledisplay means.
 11. The vehicle guidance system according to claim 9,comprising: display means for displaying on a display screen the coursearea and, of the travel courses generated by the travel coursegeneration means, a traveled travel course or courses that have alreadybeen traveled over by the vehicles; and obstacle indication means forindicating positions of obstacles on the display screen based both onrelative positional relationship thereof with the course area on thedisplay screen and on relative positional relationship with the traveledtravel course or courses on the display screen; wherein the memory meansstores the positions of obstacles on the display screen indicated by theobstacle indication means as positions of obstacles common to theplurality of vehicles; and the updating means updates the content storedin the memory means every time the position of an obstacle is newlyindicated by the obstacle display means.
 12. The vehicle guidance systemaccording to claim 9, comprising: display means for displaying thecourse area on a display screen; obstacle indication means forindicating positions of obstacles on the display screen based onrelative positional relationship thereof with the course area on thedisplay screen; and revision means for revising the positions ofobstacles indicated by the obstacle indication means, based on data onthe traveled travel course or courses over which the vehicles havealready traveled, of the travel courses generated by the travel coursegeneration means; wherein the memory means stores the obstacle positionsrevised by the revision means as positions of obstacles common to theplurality of vehicles; and the updating means updates the content storedin the memory means every time an obstacle position newly indicated bythe obstacle indication means is revised by the revision means.
 13. Avehicle guidance system comprising vehicle position measurement meansfor measuring current position of one vehicle, and being constructedsuch that, when position data for target points that should be reachedby the vehicles and position data for a course area where the vehiclecan travel are given, data for a travel course that travels inside thecourse area and passes through the target points are generated; and thesubject vehicle is guided over that travel course while comparingcurrent vehicle positions measured by the vehicle position measurementmeans and positions on the generated travel course; the vehicle guidancesystem comprising: indication means for indicating the position of amovement starting point inside the course area, the direction of avehicle at the movement starting point, the position of a target pointinside the course area, and the direction of a vehicle at the targetpoint; travel course generation means for generating travel course datawherewith the vehicle departs the movement target point in the indicatedvehicle direction, alters the direction of advance thereof, reversingdirection at one or more direction reversal points, and arrives at thetarget point in the indicated vehicle direction, so that, when positiondata indicating the boundary line of the course area are given, and theposition of the movement starting point, the vehicle direction at themovement starting point, the position of the target point, and thevehicle direction at the target point are indicated by the indicationmeans, the vehicle can travel over the interior enclosed by the boundaryline of the course area and also turn around with a turning radius equalto or greater than the minimum turning radius of the vehicle; andguidance means for causing the vehicle to be guided over the travelcourse generated by the travel course generation means.
 14. The vehicleguidance system according to claim 13, wherein the vehicle is anunmanned vehicle that is loaded with a load by a loading machine, andthe course area position data are updated by excluding a certain areareferenced to current position of the loading machine from currentcourse area.
 15. The vehicle guidance system according to claim 14,wherein the certain area excluded from the current course area is anarea within reach of the loading mechanism of the loading machine. 16.The vehicle guidance system according to claim 14, wherein the certainarea excluded from the current course area is inside an area withinreach of the loading mechanism of the loading machine, and an area ofabout size of main body of the loading machine.
 17. The vehicle guidancesystem according to claim 14, wherein the certain area excluded from thecurrent course area is inside an area within reach of the loadingmechanism of the loading machine, and an area that is located at aconstant distance from the boundary of the course area.
 18. The vehicleguidance system according to claim 13, wherein the vehicle is anunmanned vehicle that is loaded with a load by a loading machine;relative position indication means for indicating relative positionsrelative to the loading machine is provided; and position data for thecourse area are updated by excluding an area referenced to positionsindicated by the relative position indication means from current coursearea.
 19. The vehicle guidance system according to claim 13, wherein thevehicle is an unmanned vehicle that is loaded with a load by a loadingmachine, and position data for the course area are updated by adding, tocurrent course area, an area within range occupied by the unmannedvehicle at a target point that should be reached by the unmannedvehicle.
 20. The vehicle guidance system according to claim 13, whereinthe vehicle is an unmanned vehicle that is loaded with a load by aloading machine, and position data for the course area are updatedeither by excluding a certain area referenced to current position of theloading machine from current course area, or by adding area within rangeoccupied by the unmanned vehicle at target point that should be reachedby the unmanned vehicle to current course area.
 21. The vehicle guidancesystem according to claim 20, further comprising selection means forselecting whether the course area is to be expanded or contracted,according to type of work being done by the loading machine, wherein thecourse area position data are subjected to updating processing accordingto results of selection made by the selection means.
 22. An unmannedvehicle guidance system for guiding unmanned vehicles over guidancecourses based on travel positions of those unmanned vehicles measured bytravel position measurement means and course data defining guidancecourses for the unmanned vehicles; the unmanned vehicle guidance systemcomprising: means for inputting shape of a course area; means forrespectively indicating the position of a movement starting point andthe direction of advance of the unmanned vehicle at that position, andthe position of a movement target point and the direction of advance ofthe unmanned vehicle at that position; means for producing course datawherewith the indicated position and the direction of advance aresatisfied at the movement starting point and at the movement targetpoint, and wherewith the direction of advance of the unmanned vehiclechanges at one or more direction reversal points provided between themovement starting point and the movement target point; means forinferring conflicts between the course area and the unmanned vehiclewhen the unmanned vehicle is made to travel over a guidance coursedefined by the produced course data, based on data relating to theunmanned vehicle; and course data alteration means for altering thecourse data when a conflict has been inferred.
 23. The unmanned vehicleguidance system according to claim 22, wherein the means for producingcourse data comprises: means for generating position of an intermediatepoint in the guidance course inside the course area and direction ofvehicle advance at that position; and means for connecting position ofthe movement starting point, position of the intermediate point, andposition of the movement target point, with a circular arc or arcsand/or straight line or lines, so as to pass through each of thosepositions, and such that the direction of vehicle advance at each ofthose positions coincides either with direction of a tangent to suchcircular arc or arcs or with direction of such straight line or lines;wherein the course data alteration means alters the course data byaltering the position of the intermediate point when the conflict hasbeen inferred.
 24. The unmanned vehicle guidance system according toclaim 23, wherein the means for producing the course data comprises:evaluation means for evaluating the course data using distances betweenthe guidance course and boundaries of the course area; and selectionmeans for selecting course data having best evaluation values out of aplurality of generated course data.
 25. The unmanned vehicle guidancesystem according to claim 23, wherein the means for producing the coursedata comprises: evaluation means for evaluating the course data using afunction between distances between the guidance course and boundaries ofthe course area, and minimum radius of the guidance course; andselection means for selecting course data having best evaluation valuesout of a plurality of generated course data.
 26. The unmanned vehicleguidance system according to claim 22, wherein the means for producingcourse data comprises: means for generating position of an intermediatepoint in the guidance course inside the course area and direction ofvehicle advance at that position; and means for connecting position ofthe movement starting point, position of the intermediate point, andposition of the movement target point, with a spline curve, so as topass through each of those positions, and such that direction of vehicleadvance at each of those positions coincides with direction of a tangentto the spline curve; wherein the course data alteration means alters thecourse data by altering the position of the intermediate point when suchconflict has been inferred.
 27. The unmanned vehicle guidance systemaccording to claim 22, wherein the means for producing the course datacomprises: means for generating position of an intermediate point in theguidance course inside the course area and direction of vehicle advanceat that position; and means for connecting position of the movementstarting point, position of the intermediate point, and position of themovement target point, with a spline curve and a circular arc, or with aspline curve and a straight line or lines, so as to pass through each ofthose positions, and such that direction of the vehicle advance at eachof those positions coincides with direction of a tangent to that splinecurve, direction of a tangent to such circular arc, or direction of suchstraight line or lines; wherein the course data alteration means altersthe course data by altering the position of the intermediate point whensuch conflict has been inferred.
 28. The unmanned vehicle guidancesystem according to claim 22, wherein the travel position measurementmeans is a GPS, and means for inputting shape of the course areacomprises: means for switching a position measured by the GPS to aposition measured at left edge or right edge of the unmanned vehicle;and indication means for indicating whether to switch to positionmeasured at the left edge or to position measured at the right edge. 29.The unmanned vehicle guidance system according to claim 22, wherein thetravel position measurement means is a GPS, and means for inputtingshape of the course area comprises means for selectively alteringposition of antenna of the GPS to left edge or right edge of theunmanned moving body.
 30. An unmanned vehicle guidance system forguiding unmanned vehicles over guidance courses based on travelpositions of those unmanned vehicles measured by travel positionmeasurement means and course data defining guidance courses for theunmanned vehicles; the unmanned vehicle guidance system comprising:means for inputting shape of a course area; means for producing travelcourse data wherewith the unmanned vehicle alters the direction ofadvance thereof reversing direction at one or more direction reversalpoints and arrives at a target point, so that, when the shape of thecourse area is input, the unmanned vehicle can travel over the interiorenclosed by the boundary line of the course area and also turn aroundwith turning radius equal to or greater than the minimum turning radiusof the unmanned vehicle; means for inferring conflicts between thecourse area and an unmanned vehicle when that unmanned vehicle is madeto travel over a course defined by the produced course data; course dataalteration means for altering the course data when the conflict has beeninferred; and mode setting means for causing the unmanned vehicle to beguided using the generated course data when automatic operation mode hasbeen set, and for collecting course area shape data by causing theunmanned vehicle to be guided along a course area and detectingpositions traveled by the unmanned vehicle when measurement mode beenset.
 31. An unmanned vehicle guidance system for guiding unmannedvehicles over guidance courses based on travel positions of thoseunmanned vehicles measured by travel position measuring means and coursedata defining guidance courses for the unmanned vehicles, the unmannedvehicle guidance system comprising: means for inputting shape of acourse area; means for producing course data; means for inferringconflicts between the course area and the unmanned vehicle when thatunmanned vehicle is made to travel over a course defined by the producedcourse data, based on data relating to the unmanned vehicle; course dataalteration means for altering the course data when the conflict has beeninferred; means for recognizing a course area shape change zone; andcourse area shape updating means for updating shape of the course areaso that that course area shape is altered only in the shape change zone.32. The unmanned vehicle guidance system according to claim 31, whereinthe means for recognizing the shape change zone of the course areacomprises: a moving body for measuring that moves through the coursearea; movement position measurement means for measuring movementposition of the moving body for measuring; and means for specifying theshape change zone based on the movement position of the moving body formeasuring and an area occupied by that moving body.
 33. The unmannedvehicle guidance system according to claim 31, wherein the means forrecognizing the shape, change zone of the course area comprises:position measurement means for measuring three-dimensional positions ofdigging unit of a work machine for digging operations in the coursearea; ground height measurement means for measuring initial groundheight in the course area; and means for specifying the shape changezone of the course area based on position of the digging unit and areaoccupied thereby when height of the digging unit and the initial groundheight coincide.